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1

Zhang, Ling. "Butyric and docosahexaenoic acids production from hemicellulose." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13793.

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Master of Science<br>Department of Biological and Agricultural Engineering<br>Wenqiao Yuan<br>Many of the current industrial fermentation processes cannot use pentose as the carbon source. However, complete substrate utilization of sugars in lignocellulose is one of the prerequisites to render economic development of biofuels or bioproducts from biomass. In this study we proposed a new process for DHA production from renewable carbon sources by first using anaerobic bacteria, Clostridium tyrobutyricum to convert pentose into organic acids with butyric acid as the main product, and then using the organic acids to feed microalgae, Crypthecodinium cohnii to produce DHA. The effect of glucose and xylose on the yield of butyric acid produced by C. tyrobutyricum was investigated, separately. Cell growth of C. tyrobutyricum increased with increasing initial glucose or xylose concentration, but was not affected significantly when the concentration was above 55g/l for glucose or 35g/l for xylose. Butyric acid yield increased as the initial sugar concentration increased in both xylose and glucose, but the conversion rate from xylose or glucose to butyric acid decreased as the sugar concentration increased. The xylose to glucose ratio in their mixture did not significantly affect cell growth or butyric acid yield. The effect of arabinose on the yield of butyric acid produced by C. tyrobutyricum was also studied. As for butyric acid production, compared with glucose or xylose, the arabinose was in a low efficiency, with butyric acid output of 2.25g/l in 10g/l arabinose and a long lag period of about 3-4 d. However, a low concentration of arabinose could be used as a nutritional supplement to improve the fermentability of a mixture of xylose and glucose. The conversion rate of sugar to butyric acid increased as the supplement arabinose increased. In order to obtain low cost xylose, corncobs were hydrolyzed and this xylose-rich product was used to culture C. tyrobutyricum. The results showed that at end of the 9 d fermentation, the concentration of butyric acid from corncob hydrolysate reached 10.56 g/l, and the mimic medium reached 11.3 g/l. This suggests that corncob hydrolysate can be used as a carbon source for butyric acid production by C. tyrobutyricum, although some inhibitory effects were found on cell growth with corncob hydrolysate. The effect of butyric acid, lactic acid and acetic acid on the yield of DHA produced by C. cohnii was also investigated, separately. The DHA yield was highly related to both biomass and DHA content in the cell, whereas lower growth rate could bring higher DHA content. The best concentration for DHA yield seemed to be 1.2g/l in three single organic acid media. In two organic acids mixture media, acetic acid tended to be beneficial for biomass accumulation, regardless whether butyric acid or lactic acid was mixed with acetic acid, the OD could reach 1.3 or above. When butyric acid was mixed with lactic acid, the highest DHA yield was achieved, due to increased DHA content from mutual influence between butyric acid and lactic acid.
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2

Turkmenoglu, Secil. "Organic Acids Production From Cheese-whey." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12607709/index.pdf.

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In this study, production of organic acids from cheese-whey was studied. Optimization of organic acids production was performed in semi-batch and batch reactors. Two sets of experiments were performed. First set of experiments were performed in semi-batch reactors for the optimization of organic loading rate (OLR) and hydraulic retention time (HRT). As a result of Set 1 experiments optimum OLR was found to be 15 g COD l-1. Second set of experiments were performed in batch reactors by using the optimum OLR found in Set 1 experiments. Set 2 experiments were conducted to study the effect of using different seed cultures and Basal Media (BM) on Volatile fatty avid (VFA) production. Main acidogenesis products were acetic acid (Hac), butyric acid (Buty) and propionic acid (HPr) with smaller quantities of i-butyric acid (i-Buty), valeric acid (Val) and caproic acid (Cap). It was seen that BM had a suppressive effect on ethanol (EtOH) production while it stimulated the VFA production. Higher VFA productions and variety of VFA types were observed in Test Reactors seeded with acidogenic culture (R3 and R6).
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3

Sandberg, Scott Alan. "The biodegradation of valeric, butyric, propionic and acetic acids in anoxic, subsurface, soil environments." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/52069.

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The biodegradation potential of two subsurface soils was characterized by monitoring the biodegradation of short-chain fatty acids in anaerobic soil microcosms. Valerate, butyrate, propionate, and acetate concentrations were monitored independently using separate microcosms. The effect of sulfate on the microbial communities was also investigated. One soil, from Newport News, Virginia, consisted of a sandy loam collected beneath a low lying, grassy field. The microcosms containing the soil were characterized by: a neutral pH, the utilization of sulfate with concomitant precipitation of iron sulfide , an increase in the degradation rate as a result of sulfate addition, and a production of bicarbonate directly related to acid mineralization. Another soil, from Blacksburg, Virginia, consisted of a silty-clay collected beneath a wooded hilltop. Microcosms containing the soil were characterized by : a pH between 4 and 5, little sulfate utilization with no visible iron sulfide precipitation, an increase in degradation rates upon the addition of sulfate, and little or no accumulation of bicarbonate. These results indicate that short-chain fatty acids are readily degraded in subsurface anaerobic soil systems and that these rates are dependent on the availability of electron acceptors and the diversity of the indigenous population.<br>Master of Science
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4

Silva, Kelry Mayara. "Imunonutrição de frangos de corte alimentados com ácidos orgânicos em alternativa aos quimioterápicos /." Ilha Solteira, 2016. http://hdl.handle.net/11449/138284.

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Orientador: Valquíria Cação Cruz-Polycarpo<br>Resumo: A administração de ácidos orgânicos em dietas de frangos de corte pode influenciar os microrganismos e as condições do trato gastrintestinal. Para tanto, conduziu-se um experimento no qual foram utilizados 840 pintos de corte machos da linhagem Cobb®, distribuídos num delineamento inteiramente casualizado, com sete repetições e 30 aves por boxe. Os tratamentos foram: T1- dieta basal - sem inclusão de aditivo (DB) - aves não desafiadas; T2- dieta basal - sem inclusão de aditivo(DB) - aves desafiadas; T3- DB + ácidos orgânicos- aves desafiadas; T4- DB + antibiótico e anticoccidiano - aves desafiadas. Os ácidos orgânicos foram um blend composto de ácido lático (40%), ácido propiônico (5%) e ácido butírico (1%). Os frangos foram desafiados por inoculação via oral aos 11 dias de idade com Eimeria acervulina, E. máxima e E. tenella. Aos 10, 14 e 21 dias foram realizadas colheitas de sangue de aves previamente identificadas para as análises imunológicas: níveis de eritrócitos, leucócitos circulantes, proteínas totais, glicose, albumina, hematócrito, hemoglobina e contagem total de leucócitos. Os dados de desempenho foram avaliados nos períodos de 1-7,1-14, 1-21 e 1-42 dias.Com os dados de desempenho aos 42 dias, evidenciou-se a eficiência do tratamento controle negativo (sem desafio) e antibiótico + anticoccidiano, nos quais as variáveis GPM e CRM se comportaram de modo similar e melhores, em relação às dietas controle negativo (desafiadas) e inclusão de ácidos orgânicos.Os ácidos o... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The use of organic acids in chickens diets can influence gastrointestinal tract microorganisms and conditions. Therefore, a study was conducted in which 840 broiler chicks of Cobb® lineage were used, distributed in a randomized design with seven replicates and 30 birds per pen. The treatments were: T1 basal diet - without the addition of additives (DB) - unchallenged birds; T2 basal diet - without the addition of additives (DB) - challenged birds; T3 + DB organic acids challenged birds; T4 DB + antibiotic and anticoccidial - challenged birds. The organic acids were a blend composed by lactic acid (40%), propionic acid (5%) and butyric acid (1%). The chickens were challenged by oral inoculation at 11 days of age with Eimeria acervulina, E. maxima and E. tenella. At 10, 14 and 21 days blood samples were taken from previously identified birds for immunological analysis: erythrocy televels, blood leukocytes, total protein, glucose, albumin, hematocrit, hemoglobin, total leukocytes count. Performance data were evaluated in periods of 1-7, 1-14, 1-21 and 1-42 days. The performance data at 42 days showed the efficiency of the negative control treatment (no challenge) and antibiotic plus anticoccidial, where the GPM and CRM variables behave in a similar way, and therefore better than the diets of the negative control (challenged) and organic acids inclusion. Organic acids added to the diet during the breeding cycle showed no satisfactory effect on performance that characterize as a p... (Complete abstract click electronic access below)<br>Mestre
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5

Liu, Xiaoguang. "Production of butyric acid and hydrogen by metabolically engineered mutants of Clostridium tyrobutyricum." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1124114266.

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Thesis (Ph. D.)--Ohio State University, 2005.<br>Title from first page of PDF file. Document formatted into pages; contains xv, 220 p.; also includes graphics (some col.). Includes bibliographical references (p. 189-201). Available online via OhioLINK's ETD Center
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6

Poupart, Julie. "Analysis of indole-3-butyric acid auxin activity in Arabidopsis." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84312.

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Auxins are plant hormones involved in virtually all aspects of plant life. Despite long-term commercial and horticultural use of the auxin Indole-3-Butyric Acid (IBA), a full recognition of its natural occurrence in plants was made only recently. I have used multiple approaches to dissect the role of IBA in Arabidopsis thaliana. This thesis includes the first characterization of a mutant with an altered response to IBA that retains wild-type sensitivity to Indole-3-Acetic Acid (IAA), the most studied endogenous auxin. This mutant, named resistant to IBA ( rib1), has modified root architecture and gravitropism and is resistant to auxin transport inhibitors. As these phenotypes are reminiscent of those of characterized auxin transport mutants, movement of IAA and IBA was studied in wild-type and mutant plants. IBA is transported in seedlings in three distinct flows, like IAA, and this transport is saturable, indicating it is carrier mediated. However, unlike IAA, IBA is not polarly transported in inflorescence axes, and IBA transport is not sensitive to IAA transport inhibitors. These results suggest IAA and IBA transport could be mediated or regulated by different mechanisms. In rib1 seedlings, all flows of IBA transport are modified, while IAA transport levels are unchanged. Modifications in IBA transport match phenotypic differences between rib1 and wild-type, and analyses of the physiological effects of IBA also suggest IBA has a role in defining wild-type seedling morphology in Arabidopsis. Though IAA transport levels are not changed in rib1, one flow of IAA transport is rendered insensitive to IAA transport inhibitors, perhaps revealing cross-talk between IAA and IBA transport regulation. Additionally, double mutant analyses reveal that IAA transport and response mutants can suppress some phenotypes of rib1, and some mutant combinations produce novel phenotypes, further suggesting cross-talk between IBA and IAA transport and response p
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7

Merklein, Kyle. "Production of butyric acid by the cellulolytic actinobacterium Thermobifida fusca." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20555.

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Master of Science<br>Department of Biological and Agricultural Engineering<br>Mei He<br>Thermobifida fusca, an aerobic moderately thermophilic, filamentous soil bacterium is capable of producing butyric acid. Butyric acid is a 4-carbon short chain fatty acid that is widely used in the chemical, food, and pharmaceutical industries. Currently, butyric acid is primarily produced through petroleum-based chemical synthesis, but could be a candidate to be produced by fermentation. By producing through a fermentation platform, production of butyric acid can be shifted from a non-renewable to a renewable source. In an effort to make T. fusca produce a high yield of butyric acid, multiple fermentation parameters were explored and optimized. The effect of different carbon sources (mannose, xylose, lactose, cellobiose, glucose, sucrose, and acetates) on butyric acid production was studied, where cellobiose produced the highest yield of 0.67 g/g C (g-butyric acid/g-carbon input). The best stir speed and aeration rate for butyric acid production were found to be 400 rpm and 2 vvm in a 5-L fermentor. The maximum titer of 2.1 g/L butyric acid was achieved on 9.66 g/L cellulose. Fermentation was performed on ground corn stover as a substrate to evaluate the production of butyric acid on lignocellulosic biomass, and the optimized conditions resulted in a titer of 2.37 g/L butyric acid. The butyric acid synthesis pathway was identified involving five genes that catalyzed reactions from acetyl-CoA to butanyol-CoA in T. fusca. A study into the transcriptomics of T. fusca was begun by growing T. fusca under a variety of fermentation conditions, isolating the messenger RNA, and performing a sequence of the mRNA using whole transcriptome shotgun sequencing. The results of sequencing of various samples were plotted to determine correlation across numerous fermentation parameters. This correlation based analysis determined that the carbon to nitrogen ratio has the largest overall impact on gene transcription of T. fusca among all of the fermentation parameters studied. Overall, the work from this study proves that production of butyric acid is possible from a renewable cellulosic feedstock.
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8

Zhu, Ying. "Enhanced butyric acid fermentation by Clostridium tyrobutyricum immobilized in a fibrous-bed bioreactor." Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1041367406.

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Thesis (Ph. D.)--Ohio State University, 2003.<br>Title from first page of PDF file. Document formatted into pages; contains xx, 323 p. Includes abstract and vita. Advisor: Shang-Tian Yang, Dept. of Chemical Engineering. Includes bibliographical references (p. 263-288).
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9

Rendall, Stuart Neil. "An investigation into the thermal degradation of poly(3-hydroxy-butyric acid)." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323360.

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10

Asri, Narmin. "Effects of indole-3-butyric acid on the germination and growth of Glycine max (L.) Merr /." Connect to online version, 1995. http://hdl.handle.net/1989/3552.

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11

Tajarudin, Husnul Azan Bin. "A study of fatty acid production by Clostridium butyricum." Thesis, Swansea University, 2012. https://cronfa.swan.ac.uk/Record/cronfa42578.

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This thesis investigates the fatty acid production from carbohydrates using C. butyricum. In nature a common route for the anaerobic degradation of carbohydrate in the environment is via methanogenesis. At the heart of these processes however, is the metabolism of a diversity of carbohydrate materials that produce a few fatty acids (acetate and butyrate) which are then slowly converted to methane. In this context, fatty acids can be considered as a common end- product/intermediate from carbohydrate degradation that could be used to produce chemicals. Already, acetic and butyric acid are important feedstock chemicals in the pharmaceutical, food and industrial sectors and there is potential to expand this further. As a first step to investigate the conversion of waste carbohydrate to fatty acids for chemical production, C. butyricum, a strictly anaerobic bacterium, was investigated as a model system for the potential production of acetic and butyric acid. The production efficiency of C. butyricum relies on the type of substrate, production methodology, the strain and environmental conditions. Pure cultures of C. butyricum were investigated for fatty acid production from carbohydrates. Initial studies involved medium optimization in test tube culture for high growth rate and maximum biomass production (ODmax)- In this medium, glucose was selected as the main substrate together with yeast extract, KH2PO4 and NH4(SO)4. The studies were carried out in three types of pH controlled reactors; batch stirred tank (SRT), continuously stirred tank (CSTR) and membrane bioreactor (MBR) A comparison the fatty acid production kinetics and productivity in each reactor was undertaken and the effect of glucose concentration and where appropriate, glucose feed rates, were also investigated. The results show that fatty acid production could be carried out in all three fermentation systems. A common observation in these systems was that fatty acid production was influenced by the glucose concentration in that at low glucose concentration the ratio of acetate to butyrate was about 30:1 while at higher concentrations the ratio was reduced to about 3:1 on a molar basis. The detailed kinetic studies generated unique data for this organism and shows that the maintenance coefficient (ms) increase with increasing glucose concentration (0.02 to 1.1 g substrate/g cell/h), due to mainly to end product inhibition and the true yield (Yx/s was around 0.2 for all glucose concentrations tested. Meanwhile substrate saturation (KJ decreased with increasing glucose concentrations (2.06-6.41 g/L). This observation was atypical to that observed in other anaerobic fermentations by previous workers. A comparison of fatty acid productivities using a l0g/1 glucose feed in the 3 reactors for acetic acid were 0.95 g/l/h for STR. 4.41 g/l/h for CSTR and 37.88 g/l/h for MBR and for butyric acid 0.15 g/l/h for STR, 1.27 g/l/h for CSTR and 14.34 g/l/h MBR. Although, previous work in this area is limited the data obtained in this study was also compared with other published work and this suggests that the production of fatty acid, especially acetic and butyric acid in the MBR system is by far the most productive yet reported. The results are discussed in the context of the waste treatment process for fatty acid production and its application to waste conversion and its further development.
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DAMIANI, RENATA. "Influência do butirato de sódio, da cicloheximida e do cloreto de manganês na produtividade, glicosilação e propriedades biológicas da tireotrofina humana derivada de CHO." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10602.

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Made available in DSpace on 2014-10-09T12:42:23Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:02:00Z (GMT). No. of bitstreams: 0<br>Tese (Doutoramento)<br>IPEN/T<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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13

Gholizadeh, Laili. "Enhanced Butanol Production by Free and Immobilized Clostridium sp. Cells Using Butyric Acid as Co-Substrate." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19690.

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Butanol production by four different Clostridium sp. strains was investigated using glucoseP2-medium supplemented with increasing concentrations of butyric acid, added as cosubstrate.Batch fermentations were carried out in serum bottles (freely-suspended cellcultures) and fibrous-bed bioreactor (FBB) with medium recirculation (immobilized cells).Butyric acid clearly revealed to inhibit cellular growth with all specific growth rates decliningupon the increase of butyrate concentrations. However, the presence of low and moderatelevels in the medium can readily enhance the ABE-fermentation and increase butanolproduction through a shift induction towards the solventogenic phase controlled by themedium pH. In all cases it was found that 4.0 g⋅l-1 is the optimal concentration of butyratethat maximizes the yields for all ABE-solvents and butanol productivities. The non-mutant C.acetobutylicum ATCC 824 was singled out as the most efficient butanol productive strainamong all bacteria tested (10.3 g⋅l-1 butanol versus 0.72 g⋅l-1 with and without 4.0 g⋅l-1butyrate, respectively) showing a productivity augment in the order of 0.078 g⋅l-1⋅h-1 (78.5%)and yields of 0.3 g⋅g-1 from substrate and 7.6 g⋅g-1 from biomass versus 0.072 g⋅g-1 and 0.41g⋅g-1 with and without the optimal butyrate concentration, respectively. This strain alsorevealed the best overall tolerance over increasing butyrate concentrations up to ∼6.0 g⋅l-1 andthe highest glucose uptake (65.5%) among all bacteria. Furthermore, the beneficial effects ofbutyric acid were also observed through the use of a fibrous bed-bioreactor when the mutatedstrains of C. beijerinckii ATCC 55025 and BA 101 were tested. The use of this immobilizedcell system effectively improved butanol production over the free system with butanol titersin the fermentation broth around 11.5 g⋅l-1 and 9.4 g⋅l-1 for the two bacteria, respectively,roughly doubling the values attained with the corresponding suspended cell cultures when themedia were supplemented with 4.0 g⋅l-1 of butyrate. All these results confirm theenhancement of butanol formation using either free or immobilized cell culturessupplemented with butyric acid concentrations up to 4.0 g⋅l-1 in the media.
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Huq, Abul Fatha Md Anisul. "Interfacial and Solvent Processing Control of Phenyl-C61-Butyric Acid Methyl Ester (PCBM) Incorporated Polymer Thin Films." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427746818.

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15

Jordan, Russell S. (Russell Stall). "Investigation of Inhibitory Influences in Neuronal Monolayer Networks Cultured from Mouse Spinal Cord." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc500431/.

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The effects of the inhibitory neurotransmitters gammaamino butyric acid (GABA) and glycine were characterized on spontaneous activity recorded from mouse spinal cord cultures. The GABA concentration which completely inhibited burst activity was chosen as a quantifiable measure of culture drug response and was used to 1) assess interculture and intraculture variability, 2) determine the influence of culture age and initial activity on GABA responses, and 3) compare the GABA responses between networks obtained from whole spinal cord and ventral half spinal cord. Results showed that 1) no significant variability existed either within or among cultures, 2) the initial culture activity directly affected GABA responses, 3) the culture age had no effect on GABA responses, and 4) there was no significant difference in GABA responses between the two spinal cord tissues.
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16

Amponsah, Yvonne. "In situ product recovery of butanol and butyric acid from fermentation processes using gas stripping and reverse osmosis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Two types of in situ product recovery processes are investigated: gas stripping for solvent removal in continuous butanol fermentation and reverse osmosis for acid separation and purification in a continuous butyric acid fermentation. Gas stripping and reverse osmosis are easy to operate and design processes that can be integrated to fermentation processes.
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17

Rabelo, Camila Abreu Borges da Silva. "Avaliação de consórcio microbiano obtido a partir de lodo de estação de tratamento de efluentes de indústria de papel e celulose visando à produção de H2 a partir de celulose." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-27082014-101112/.

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Ensaios em reator em batelada foram conduzidos para avaliar a produção biológica de hidrogênio a partir de diferentes concentrações de celulose (E1:2,0 g.L-1; E2: 5,0 g.L-1 e E3: 10,0 g.L-1) em pH inicial de 6,8 a 37°C. O objetivo do trabalho foi analisar o lodo de estação de tratamento de efluentes de indústria de papel e celulose como inóculo para obtenção de um consórcio celulolítico e fermentativo. Os ensaios foram monitorados por 16 dias com análises de carboidratos, DQO, pH, ST, STV, biogás, ácidos orgânicos e álcoois, além de análises de caracterização filogenética do Domínio Bacteria. Nos três ensaios, a produção de hidrogênio foi detectada a partir do quarto dia, provavelmente devido ao tempo necessário para hidrólise da celulose. Os dados de produção de hidrogênio foram ajustados ao modelo de Gompertz modificado, sendo calculado o potencial máximo de produção de H2 (P) de 1,23 mmol para E1, 3,14 mmol para E2 e 2,33 mmol para E3. Para os ensaios E1 e E2 observou-se rendimentos de H2 semelhantes; ou seja, de 0,62 mmol H2.g-1 de celulose. Para o ensaio E3 observou-se 0,23 mmol H2.g-1 de celulose. Ácido butírico foi o principal ácido orgânico observado em 2,2, 1,8 e 2,2 g.L-1 para E1, E2 e E3, respectivamente. A fase de diminuição da produção de H2 foi acompanhada pela evolução de metano, ácido acético e sulfeto nos três ensaios. Na visualização microscópica de amostras dos ensaios foi possível averiguar a presença de variedade de formas e arranjos bacterianos corroborando para heterogeneidade do inóculo. Em relação à análise filogenética foram identificados, com mais de 95% de similaridade, gêneros de bactérias reconhecidamente produtoras de H2 e associadas a ambiente com substratos lignocelulósicos, tais como, Clostridium sp., Klebsiella sp. e Raoultella sp., além de consumidoras de H2 Clostridium sp., por homoacetogênese e Desulfovibrio sp. por sulfetogênese. A partir das análises dos resultados, foi possível afirmar que houve produção biológica de hidrogênio a partir de celulose como substrato e lodo de ETE industrial como inóculo.<br>Batch assays in anaerobic reactors were conducted to evaluate the biological production of hydrogen from different concentrations of cellulose ( E1: 2.0 g.L-1; E2: 5.0 g.L-1 and E3: 10.0 g.L-1) in initial pH of 6.8 at 37 ° C. The aim of this study was analize the sludge of a treatment plant of pulp and paper industry wastewater as inoculum in the anaerobic reactors. The assays were monitored for 16 days by analyses of total soluble carbohydrates, COD, pH, TS, TVS, biogas and organic acids and alcohols. Phylogenetic characterization was carried out for microrganisms of the Bacteria Domain by cloning and sequencing analysis. The hydrogen production was detected on the fourth day of the incubation for the three experimental conditions, probably due to the period required for cellulose hydrolysis. Hydrogen production data were adjusted to the modified Gompertz model, and the maximum hydrogen production potential (P) were 1.23 mmol for E1, 3.14 mmol for E2 and 2.33 mmol for E3. Similar hydrogen yields were observed for assays E1 and E2; ie 0.62 mmol H2.g-1 of cellulose. For E3 the yield was 0.23 mmol H2.g-1 cellulose. Butyric acid was the major organic acid observed with 2.2, 1.8 and 2.2 g.L-1 to E1, E2 and E3, respectively. Hydrogen depletion in the biogas was accompanied by the evolution of methane, acetic acid and sulfide in the three tests. By means of microscopic visualization of microrganisms samples it was possible to determine the presence of a variety of bacterial shapes and confirming the heterogeneity of the inoculum. Regarding phylogenetic analysis, there were identified, with more than 95% similarity, genera of bacteria known as hydrogen producers or related with environments associated with lignocellulosic substrates such as Clostridium sp. Klebsiella sp. and Raoultella sp., consuming genere were also detedted, such Clostridium sp. by homoacetogênese and Desulfovibrio sp. by sulfidogenesis.
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18

Wersinger, Eric. "Inhibition présynaptique et contraste dans la rétine de souris : à la recherche du rôle des dystrophines." Paris 6, 2007. http://www.theses.fr/2007PA066122.

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Ce travail visait à étudier la neurotransmission dans la première synapse de la rétine, ou l’inhibition latérale permet un renforcement du contraste spatial et de la perception des bords des objets. Or, la nature de son mécanisme n’est pas connue à ce jour. L’utilisation de techniques d’électrophysiologie, d’immunohistochimie et de biologie moléculaire nous a permis de démontrer, à partir d’une étude comparative sur quatre souches de souris, qu’une forte proportion de cellules horizontales expriment la GAD65, mais contiennent du GABA uniquement chez la souris Balb/c. Notre approche pour mettre en évidence une transmission GABA, a permis de révéler la présence du transporteur du glutamate EAAT5 dans les cellules bipolaires à bâtonnet. Son activation permet un rétrocontrôle rapide renforçant le contraste dans la voie des bâtonnets. Enfin, nous avons apporté de nouveaux éléments pour comprendre le rôle des dystrophines dans la première synapse, et dont l’absence conduit à un défaut de transmission.
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Ozsoy, Burcu. "Hydrogen And Poly-beta Hydroxy Butyric Acid Production And Expression Analyses Of Related Genes In Rhodobacter Capsulatus At Different Acetate Concentrations." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614076/index.pdf.

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Hydrogen, which is a clean energy source, is one of the alternatives for fossil fuels. Biological hydrogen production is one of the hydrogen production methods. Rhodobacter capsulatus is a photosynthetic bacterium that produces hydrogen via photofermentation. R. capsulatus can also synthesize some valuable by-products such as Poly-beta- hydroxy butyric acid (PHB), which is a biodegradable bioplastic. In a two stage biohydrogen production system, which is combination of dark fermentation and photofermentation, dark fermentor effluents are used for photofermentation by R.capsulatus. Dark fermentor effluents usually contain high amount of acetate. High amount of acetate may decrease the efficiency of hydrogen production by causing high amount of PHB production. Therefore, it is significant to determine optimum acetate concentration for photofermentation. In this study, the effects of acetate concentration on hydrogen and PHB production by R.capsulatus were investigated by growing bacteria at various acetate concentrations (10 mM-65 mM). In addition, gene expression analysis was performed to investigate the effects of acetate at transcriptional level. For this purpose, expression levels of the genes that encode nitrogenase which is the enzyme that catalyzes hydrogen production and PHB synthase, which is the key enzyme of the PHB synthesis pathway, are examined. Optimum acetate concentration for photofermentation with high hydrogen yield and low PHB amount was determined to be in the range 25 mM-50 mM. nifD expression was found to be high at optimum acetate concentrations and phaC expression was found to be the highest at 65 mM.
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Faulhaber, Michaela Sharon. "Encapsulated butyric acid and bacillus subtilis as antibiotic substitutes to mitigate heat stress and promote gut health and perfomance in broilers." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/77815.

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The removal of in-feed antibiotics has created increased focus on the potential alternatives to replace antibiotic growth promotors. With rise in global warming and the inability of birds to efficiently dissipate heat, the need to find ways to reduce the incidence and risk associated with heat stress is important by modulating the gut to reduce the negative impacts caused by heat stress. Probiotics and encapsulated butyric acid have shown promise as alternatives to antibiotics as well as potential mitigators of the effect of heat stress on the gut health and performance in broilers. The study aimed to determine the response of broiler chickens supplemented with encapsulated butyric acid and B. subtilis combined and alone against zinc bacitracin with the intention of improving overall gut health, the microbiome composition and growth performance and to mitigate the effect of heat stress in male broilers. One thousand nine hundred and twenty (1920) day-old male Ross 308 chicks were distributed amongst two environmentally controlled houses which were either at heat stress conditions or thermoneutral conditions. Both houses were run simultaneously and consisted of six dietary treatments with eight replications per treatment and twenty broilers per pen. The dietary treatments were as follows: basal diet; basal diet with zinc bacitracin; basal diet with encapsulated butyric acid (EBA); basal diet with zinc bacitracin and encapsulated butyric acid; basal diet with a B. subtilis-based probiotic; and basal diet with B. subtilis and encapsulated butyric acid. Production parameters were observed on a weekly basis. On day 21 and 35, two birds per pen were euthanised and samples of the small intestine and digesta were collected for histomorphological and microbiome analysis, respectively. Overall gut health was also scored. Dietary inclusion of B. subtilis in combination with EBA revealed no significant improvement in growth performance although results were comparable to the antibiotic treatment. Thermotolerance of the birds were improved by the inclusion of a combination of B. subtilis and EBA. Protection of the gut integrity, villi-crypt structure and intestinal microbiota environment also ameliorated the adverse effect of heat stress on gut health, resulting in growth performance being comparable to AGP.<br>Dissertation (MSc (Agric))--University of Pretoria, 2019.<br>Animal and Wildlife Sciences<br>MSc (Agric)<br>Unrestricted
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Kalia, Veena. "Hypothalamic dopamine (DA), 5-hydroxytrytamine (5-HT) and (220)-amino butyric acid (GABA) in control of lutenising hormone release in the ovariectomised rat." Thesis, St George's, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300612.

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Rahal, Naim. "Contribution à l'étude des propriétés d'une solution liquide ternaire au voisinage de la démixtion." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209464.

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Le système ternaire eau-acide butyrique- pentan-2-ol est utilisé comme système modèle pour l’étude de système plus complexe. Ce système est utilisé pour étudier les couplages diffusifs quand les constituants sont distribués sur plusieurs phases. Ses molécules simples permettent de ne pas mettre en avant les effets stériques dus à de longues chaines carbonées ou entropiques dus à des importantes différences de masse moléculaire. <p>Les couplages de la diffusion avec la solubilité permettent d’observer toute une gamme de phénomènes allant de présence de turbidité ou de gouttelettes au sein de la phase aqueuse jusqu’au maintien de gradient de concentration bien au-delà du temps caractéristique de diffusion. Ces différents phénomènes ont été observés grâce à une expérience où l’on superpose deux phases de liquide, l’une de pentan-2-ol pur et l’autre d’un mélange d’eau et d’acide butyrique.<p>La solubilité du système est déterminée par une méthode RMN. Cette technique permet également d’obtenir les variations de l’environnement intermoléculaire avec la composition de la solution et de mettre en évidence des structures au sein du liquide. <p>Enfin les coefficients de self diffusion a été mesuré par méthode DOSY pour les liquides purs, les mélanges binaires et ternaires.<p><br>Doctorat en Sciences de l'ingénieur<br>info:eu-repo/semantics/nonPublished
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23

Brock, Justin Alan. "Rooting stem cuttings of shantung maple (Acer truncatum), mound layering shantung and caddo sugar maples (Acer saccharum), and using Eastern redcedar (Juniperus virginiana) as a substrate component in stem cutting propagation." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17575.

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Master of Science<br>Department of Horticulture, Forestry, and Recreation Resources<br>Jason J. Griffin<br>Heat and drought tolerance make shantung maple (Acer truncatum) and caddo sugar maple (A. saccharum) good candidates for midwestern landscapes. Improving cutting propagation or mound layering techniques could increase the availability of these species. The influence of time of year, cutting position, and auxin concentration, formulation, and solvent on rooting of stem cuttings of shantung maple was investigated. Semi-hardwood cuttings rooted best (55%). Generally, rooting percentage decreased as indole-3-butyric acid (IBA) concentration increased. Cutting position, auxin formulation, and solvent did not affect rooting. Mean root number and mean root length were unaffected by treatments. Results suggest semi-hardwood cuttings and low IBA concentrations [< 2500 ppm (0.25%)] promote rooting. Auxin concentration influenced rooting of caddo and shantung maple mound layered shoots. Rooting peaked at 15,000 ppm (1.5%) IBA for both caddo (71%) and shantung maples (34%). Mean root number for caddo, but not shantung, increased as IBA concentration increased. Differences in mean root length were not significant. Growers may now propagate caddo maple by mound layering. For shantung maple propagation, stem cuttings are recommended. Propagation substrates can strongly influence rooting success of stem cuttings. Eastern redcedar (Juniperus virginiana) chips (ERC) have been suggested as a propagation substrate component. This report investigated ERC as a perlite substitute in a 3 perlite: 1 sphagnum peat moss (v/v) rooting substrate. Stem cuttings of spreading euonymus (Euonymus kiautschovicus), forsythia (Forsythia x intermedia), English ivy (Hedera helix), lantana (Lantana camara), and coleus (Solenostemon scutellarioides) were rooted in substrates containing increasing concentrations of ERC hammer milled to pass a 4.8 mm (0.19 in) screen. All species rooted well (≥95%) in all substrates except forsythia which rooted poorly in all substrates (8% to 36%). ERC did not affect mean root number or mean root length in any species except spreading euonymus where mean root number peaked at 0% and 100% ERC content and mean root length decreased with increasing ERC content. Bulk density, container capacity, and total porosity increased as ERC replaced perlite. Physical properties of all substrates were suitable for cutting propagation. ERC can effectively replace perlite in rooting substrates for many ornamental species.
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Allemann, Monika. "Effect of sodium butyric- and valerianic acid on contractility of ex-vivo intestinal wall specimens from the cecum and spiral colon of healthy cows /." [S.l.] : [s.n.], 1999. http://www.stub.unibe.ch/html/haupt/datenbanken/diss/bestell.html.

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van, Pelt Thomas. "Thin films of [6,6]-phenyl-C61-butyric acid methyl ester for application in organic solar cells : preparation and effects of exposure to light and heat." Thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-27500.

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26

Bellion, Arnaud. "Régionalisation du cortex cérébral et mode de migration des interneurones corticaux." Paris 6, 2002. http://www.theses.fr/2002PA066390.

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Fadel, James R. "Modulation of cortical acetylcholine release by glutamate, gamma-amino butyric acid, and noradrenaline receptor mechanisms within the basal forebrain : studies on basal and behaviorally-activated release /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487953204280146.

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28

Chaves, Elisiane Inês Dall'oglio. "Estabelecimento "in vitro" de Citronela de Java (Cymbopogon winterianus Jowitt)." Universidade Estadual do Oeste do Paraná, 2006. http://tede.unioeste.br:8080/tede/handle/tede/1282.

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Made available in DSpace on 2017-07-10T17:37:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-19<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>Citronella of Java (Cymbopogon winterianus Jowitt) is an aromatical plant with large usage in the manufacture of mosquito repellents because it contains essential oil rich in citronelal. The application of tissue culture on a large scale in medicinal plants production has increased significantly, since the conventional methods of propagation limit the potential use of some plants. Due that, one citronella of Java protocol was established with the objective of getting an alternative technique for the propagation of that culture. Four experiments ware conducted to evaluate the asepsis time, the explant type, the effect of vegetal regulators on the "in vitro" propagation of citronella of Java, as well as the micro-propagated seedling acclimatization. The gotten results had disclosed that the use of sodium hypochlorite (0.5%) during 30 minutes promoted a satisfactory asepsis index. The shoot tips explants type showed greater potential for the ?in vitro? development. It was verified that the use of benzilaminapurine (BAP) cytokynin is indispensable to succeed in the citronella of Java "in vitro" establishment, being able to be used in the concentration of 2.0 mg L-1. However, the use of indolbutyric acid (IBA) in the different tested concentrations did not present any results that justify its use, neither in the citronella of Java multiplication nor in the root establishment. The root establishment was evidenced when micro-propagated seedlings had been inoculated only in MS culture medium. It was verified that the check (without vegetal regulator) had a direct organogenesis, while such event was not verified in the other treatments. In the micro-propagated seedling acclimatization it was verified that the use of the floating method, it was essential for the seedlings survival, resulting in high survival index<br>A citronela de Java (Cymbopogon winterianus Jowitt) é uma planta aromática muito utilizada na fabricação de repelentes contra mosquitos por conter óleo essencial rico em citronelal. A utilização da cultura de tecidos, como forma de propagação de plantas medicinais tem aumentado significativamente, pois os métodos convencionais de propagação limitam o potencial de uso de algumas plantas. Sendo assim, um protocolo regenerativo para a citronela de Java foi estabelecido com o objetivo de se obter uma técnica alternativa para a propagação dessa cultura. Para isso foram realizados quatro experimentos envolvendo a avaliação do tempo de assepsia, do tipo de explante, do efeito de reguladores vegetais na propagação in vitro da citronela de Java, bem como a aclimatação das plântulas micropropagadas. Os resultados obtidos revelaram que a utilização do hipoclorito de sódio (0,5%) por 30 minutos promoveu índice satisfatório de assepsia. Os explantes com maior potencial ao desenvolvimento in vitro foram os ápices caulinares. Verificou-se que o emprego da citocinina benzilaminopurina (BAP) é indispensável para o sucesso do estabelecimento in vitro da citronela de Java, podendo ser utilizado na concentração de 2,0 mg L-1. No entanto, a utilização do ácido indolbutírico (IBA) nas diferentes concentrações testadas não apresentou resultados que justifique seu emprego, tanto na multiplicação quanto no enraizamento das plântulas de citronela de Java. O enraizamento foi evidenciado quando as plântulas micropropagadas foram inoculadas somente em meio de cultura MS. Foi constatado que na testemunha (sem regulador vegetal) houve uma organogênese direta, não sendo verificada nos demais tratamentos. Na aclimatação das plântulas micropropagadas verificou-se que a utilização do método floating , foi fundamental para a sobrevivência das plântulas, tendo sido observado alto índice de sobrevivência
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Matos, Thaisa Moreira de. "Catalisadores de Ni suportados em Al2O3 modificados com V, Nb e Zn aplicados na reforma à vapor do ácido butírico para produção de H2." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-22052017-081023/.

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O hidrog&ecirc;nio &eacute; visto como um importante combust&iacute;vel alternativo aos combust&iacute;veis convencionais, como a gasolina e o &oacute;leo diesel, devido a sua alta efici&ecirc;ncia energ&eacute;tica e n&atilde;o gera&ccedil;&atilde;o de poluentes. Por&eacute;m, a maior parte do hidrog&ecirc;nio produzido &eacute; proveniente de fontes n&atilde;o renov&aacute;veis, como o g&aacute;s natural e o petr&oacute;leo. Novas tecnologias para a gera&ccedil;&atilde;o de hidrog&ecirc;nio vem sendo estudadas e dentre elas se destaca a rea&ccedil;&atilde;o de reforma a vapor de compostos oxigenados. Os &aacute;cidos graxos vol&aacute;teis gerados durante o tratamento anaer&oacute;bio de &aacute;guas residu&aacute;rias constitui uma mat&eacute;ria-prima interessante para a produ&ccedil;&atilde;o de hidrog&ecirc;nio a partir de biomassa. Os principais produtos gerados no tratamento de &aacute;guas residu&aacute;rias s&atilde;o o etanol, o &aacute;cido ac&eacute;tico e o &aacute;cido but&iacute;rico, este, chega a representar 35 % em massa podendo ser utilizado como mol&eacute;cula modelo na rea&ccedil;&atilde;o de reforma a vapor. Neste trabalho, foram desenvolvidos catalisadores a base de n&iacute;quel (Ni) modificados com van&aacute;dio (V), zinco (Zn) e ni&oacute;bio (Nb) suportados em alumina (&#947;-Al2O3), visando minimizar os dep&oacute;sitos carbon&aacute;ceos, assim como aumentar a atividade e seletividade para o hidrog&ecirc;nio na rea&ccedil;&atilde;o de reforma a vapor do &aacute;cido but&iacute;rico. Os catalisadores foram modificados com diferentes teores de V, Zn e Nb (2,5, 5 e 10 % em massa). Nas rea&ccedil;&otilde;es feitas a 600 &ordm;C utilizando raz&atilde;o estequiom&eacute;trica &aacute;cido but&iacute;rico:vapor, dentre os catalisadores modificados com V, o com 5 % (10Ni2,5VAl2O3) apresentou o melhor desempenho, chegando a uma convers&atilde;o de 86 % para o &aacute;cido but&iacute;rico, al&eacute;m de aumentar a estabilidade do catalisador quando comparado ao catalisador contendo apenas Ni (10NiAl2O3). Para o grupo de catalisadores modificados com Zn, o catalisador com 10 % em massa de Zn (10Ni10ZnAl2O3) apresentou uma convers&atilde;o de 83 %, sendo este grupo o com menor taxa de forma&ccedil;&atilde;o de carbono. Dentre os catalisadores modificados com Nb, o com menor teor (10Ni2,5NbAl2O3) foi o que apresentou o melhor desempenho, alcan&ccedil;ado uma convers&atilde;o de 82 %. Testes catal&iacute;ticos utilizando excesso de &aacute;gua mostraram alta convers&atilde;o, superiores a 90 %, e alta seletividade para H2. Dessa forma, a adi&ccedil;&atilde;o de metais com diferentes propriedades pode contribuir para uma maior seletividade para hidrog&ecirc;nio, seja pela redu&ccedil;&atilde;o dos dep&oacute;sitos de carbono ou pela melhora na estabilidade catal&iacute;tica.&#8195;<br>Hydrogen is an important alternative fuel to conventional fuels, such as gasoline and diesel, due to its high energy efficiency and non-generation of pollutants. However, most of the hydrogen produced comes from non-renewable sources such as natural gas and diesel oil. New technologies for the generation of hydrogen have been studied, among them the reaction of steam reforming of oxygenated compounds. Volatile fatty acids generated during the anaerobic treatment of wastewater are an interesting raw material for the production of hydrogen from biomass. The main products generated in the treatment of wastewater are ethanol, acetic acid and butyric acid, which represents 35% by mass and can be used as a model molecule in the steam reforming reaction. In this work, nickel-based (Ni) catalysts modified with vanadium (V), zinc (Zn) and niobium (Nb) supported on alumina (&#947;-Al2O3) were developed, aiming at minimizing carbonaceous deposits, as well as increasing activity and selectivity for the hydrogen in the steam reforming reaction of butyric acid. The catalysts were modified with different levels of V, Zn and Nb (2.5, 5 and 10 % by mass). In the reactions made at 600 &ordm;C using stoichiometric butyric acid: steam ratio, among the catalysts modified with V, the 5 % (10Ni2,5VAl2O3) showed the best performance, reaching a conversion of 86 % to butyric acid, besides increasing The stability of the catalyst when compared to the catalyst containing only Ni (10NiAl2O3). For the group of catalysts modified with Zn, the catalyst with 10 % by mass of Zn (10Ni10ZnAl2O3) showed a conversion of 83 %, this group being the one with the lowest rate of carbon formation. Among the catalysts modified with Nb, the one with the lowest content (10Ni2,5NbAl2O3) was the one that presented the best performance, achieving a conversion of 82 %. Catalytic tests using excess water showed high conversion, higher than 90%, and high selectivity for H2. Thus, the addition of metals with different properties may contribute to a higher selectivity for hydrogen, either by reducing carbon deposits or by improving catalytic stability.
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30

Köppel, Alica [Verfasser]. "Das synthetische Chaperon Phenyl-Butyric-Acid (PBA) verändert das Verteilungsmuster der HBV-Hüllproteine im Endoplasmatischen Retikulum von Hepatitis B-transgenen Mäusen und führt zu verstärkter Pathogenese / Alica Anna Maria Köppel." Gießen : Universitätsbibliothek, 2019. http://nbn-resolving.de/urn:nbn:de:hebis:26-opus-146922.

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Köppel, Alica Anna Maria [Verfasser]. "Das synthetische Chaperon Phenyl-Butyric-Acid (PBA) verändert das Verteilungsmuster der HBV-Hüllproteine im Endoplasmatischen Retikulum von Hepatitis B-transgenen Mäusen und führt zu verstärkter Pathogenese / Alica Anna Maria Köppel." Gießen : Universitätsbibliothek, 2019. http://d-nb.info/1190031086/34.

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32

Gérard, Philippe. "La rubredoxine de Clostridium butyricum : clonage et caractérisation du gène : étude de son expression en différentes conditions de croissance." Nancy 1, 1999. http://www.theses.fr/1999NAN10247.

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Les rubrédoxines sont définies comme des protéines fer-soufre ne contenant pas de soufre inorganique et caractérisées par la présence de fer lié par quatre résidus cystéine. Cette petite protéine a été isolée à partir de nombreuses bactéries anaérobies et de deux bactéries aérobies (Pseudomonas oleovorans et Acinetobacter calcoaceticus). Bien que sa structure soit bien connue et qu'elle soit considérée comme un transporteur d'électron, sa fonction n'a été établie que chez trois micro-organismes dont les deux bactéries aérobies. En utilisant des oligonucléotides amorces issus de la séquence du gène de la rubrédoxine de Clostridium pasteurianum, nous avons détecté la présence de ce gène chez 11 souches de Clostridium butyricum. Le séquençage des 11 fragments de PCR a montré que ce gène est présent sous trois formes différentes chez cette espèce clostridiale. [. . . ]
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33

Ríos, Alcaraz Francisco Abraham. "Obtenção de consórcio de bactérias fotoheterotróficas geradoras de H2 visando sua produção em reator anaeróbio em batelada /." Araraquara, 2016. http://hdl.handle.net/11449/138030.

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Orientador: Sandra Imaculada Maintinguer<br>Resumo: A bioconversão de diferentes materiais orgânicos em hidrogênio é uma tecnologia sustentável. Inóculos de climas tropicais, como o Brasil, com temperaturas médias de 25°C podem favorecer o crescimento bacteriano. A geração de hidrogênio com consórcios bacterianos têm vantagens sobre culturas puras quanto aplicado no tratamento de águas residuárias. O hidrogênio pode ser gerado em duas fases durante os processos anaeróbios. Em primeiro lugar, hidrogênio e ácidos orgânicos podem ser produzidos por processos fermentativos. Esses ácidos gerados podem ser usados por bactérias fotoheterotróficas na segunda fase, durante a operação dos reatores anaeróbios na presença de luz. O objetivo deste estudo foi avaliar o potencial de produção hidrogênio a partir de resíduos orgânicos por consórcios de bactérias fotoheterotróficas. Foram feitos 12 ensaios (I-XII) separadamente, em triplicatas de reatores anaeróbios em batelada, em meio de cultivo Rhodospirillaceae, headspace N2 (100%), pH 7.0+1, a 37ºC. Foram comprovados os efeitos com duas potências de intensidade de luz (8,8±1 e 18,5±1 W/m2) e diferentes concentrações de ácidos butírico, acético, além de efluentes de processos fermentativos procedentes de glicerol bruto e águas residuárias citrícolas. As condições ótimas para a produção de hidrogênio foram de 18.5±1 W/m2 de intensidade de luz e 1.7 g/L para o ácido acético (II), 1.0 g/L para o ácido butírico (V), 1.0 g de COD/L de glicerol efluente (IX), e 0.5 g de DQO/L para o efluente de á... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The bioconversion of different organic materials to hydrogen is a sustainable technology. Inocula from tropical climates such as Brazil which average temperatures around 25°C may favour the bacterial growth. Hydrogen generation with bacterial consortia have advantages over pure cultures regarding application to wastewater treatment. The hydrogen can be generates in two stages during the anaerobic processes. Firstly, hydrogen and organic acids can be produced by dark fermentation. The acids generated during the first stage of the fermentation process can be used by phototrophic bacteria in the second stage during the operation of anaerobic batch reactors on the light presence. The aim of this study was evaluate the hydrogen producing potential from organic wastes by phototrophic bacterial consortia. Assays (I - XII) were made separately in triplicates of anaerobic batch reactors, Rhodospirillaceae medium (Chi Mei Lee, 2005), headspace with N2 (100%), pH 7.0+1, at 37oC. Effects with two potencies of light intensity (8.8±1 and 18.5±1 W/m2 ) and different concentrations of butyric acid, acetic acid and dark fermentation effluents from crude glycerol and citrus wastewaters were optimized. The optimal conditions for hydrogen production from phototrophic consortia were 18.5±1 W/m2 of light intensity and 1.7 g/L for acetic acid (II), 1.0 g/L for butyric acid (V), 1.0 g COD/L for Glycerol effluent (IX), and 0.5 g COD/L for citrus wastewater effluent (XII). Under the optimum conditions... (Complete abstract click electronic access below)<br>Mestre
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Rabelo, Camila Abreu Borges da Silva. "Otimização da produção de hidrogênio e ácidos orgânicos em reator em batelada a partir de consórcio de bactérias autóctones e alóctones do bagaço de cana-de-açúcar." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-16042018-163435/.

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Nessa pesquisa avaliou-se a produção fermentativa de hidrogênio e ácidos orgânicos a partir do bagaço de cana-de-açúcar (BCA) usado como substrato em reatores em batelada. Três condições de pré-tratamento (hidrotérmico, autoclave e hidrotérmico mais autoclave) do BCA e condição in natura foram avaliadas a fim de favorecer a produção de hidrogênio. Verificou-se produção molar de hidrogênio de 3,79 mmol/L, 3,47 mmol/L, 1,67 mmol/L e 1,01 mmol/L para BCA autoclavado, BCA in natura, BCA pré-tratado em sistema hidrotérmico e BCA pré-tratado em sistema hidrotérmico seguido de autoclave, respectivamente. A partir desses valores, optou-se por usar o BCA autoclavado como substrato para otimização da produção de hidrogênio e ácidos orgânicos a partir de metodologias de delineamento do composto central e superfície de resposta. Foram monitorados 10 reatores em batelada (R1 a R10), em triplicatas, com diferentes concentrações de substrato (0,8 a 9,2 g/L) e pH (de 4,6 a 7,4). A maior produção de hidrogênio (24,1 mmol/L) e 6,4 g/L de ácidos orgânicos foram obtidos em R4 (8,0 g BCA/L e pH 7,0). Os açúcares glicose, arabinose, xilose, manose e galactose foram observados ao longo do tempo de operação em todos os reatores, sendo arabinose observado em maior concentração nas condições dos reatores R3 (8,0 g BCA/L e pH 5,0) e R8 (5,0 g BCA/L e pH 7,4), respectivamente, 1.415,3 e 1.372,5 mg/L. A produção de hidrogênio foi concomitante à formação de ácidos orgânicos, principalmente butírico (de 14,6 a 33,8% em R1 e R6, respectivamente) e succínico (de 19,5 a 26,4% em R3 e R9, respectivamente). Os dois fatores analisados, concentração de substrato e pH, exerceram efeitos significativos na produção de hidrogênio, ácido butírico e succínico. A partir dos resultados obtidos com o planejamento fatorial, foi possível verificar que o valor máximo de produção de hidrogênio estimado pelo modelo foi de 23,10 mmol/L, para 7,0 g BCA/L e pH 7,2. O valor obtido no experimento de otimização (Rotm) foi de 19,84 mmol/L, com grau de precisão do modelo de 85,9% para produção de hidrogênio a partir de BCA autoclavado. Sequenciamento massivo via plataforma Illumina (Miseq) foi realizado para a identificação de bactérias do reator do ponto central, (R9, 5,0 g BCA/L e pH 6,0), do reator otimizado (Rotm, 7,0 g BCA/L e pH 7,2), de amostras do BCA autoclavado e inóculo. No inóculo foram identificadas principalmente bactérias semelhantes a Clostridium bifermentans (62,69% de abundância relativa), Bacillus coagulans (31,67%) e Enterobacter aerogenes (2,72%). No BCA foram identificadas bactérias semelhantes a C. bifermentans (31,91%), C. cellobioparum (32,29%), C. cellulolyticum (5,69%), C. sartagoforme (14,63%) e Paenibacillus spp. (11,67%). Estas bactérias não foram favorecidas sob as condições impostas em R9 (5,0 g BCA/L e pH 6,0) e Rotm (7,0 g BCA/L e pH 7,2), uma vez que a abundância relativa das bactérias nas amostras dos reatores foram completamente diferentes. Em R9, bactérias semelhantes a Lactobacillus paracasei e Escherichia hermannii foram as principais identificas com 37,50 e 34,32% de abundância relativa, respectivamente. Em Rotm, as principais bactérias identificadas foram semelhantes a Bacteroides sp. e Enterobacter aerogenes, com 37,35 e 27,72% de abundância relativa, respectivamente. Assim, as populações bacterianas, bem como a produção de metabólitos, foram alteradas em função das condições impostas; ou seja, concentração de BCA, pH em reatores em batelada com BCA autoclavado como substrato.<br>This study evaluated the hydrogen and organic acids fermentative productions from sugarcane bagasse (SCB) as substrate in batch reactors. Three pre-treatment conditions (hydrothermal, autoclave and hydrothermal plus autoclave) of BCA and the in natura condition were evaluated in order to favor the hydrogen production. Hydrogen molar productions of 3.79 mmol/L, 3.47 mmol/L, 1.67 mmol/L and 1.01 mmol/L was found for SCB pretreated in autoclave, BCA in natura, SCB pretreated in hydrothermal system and SCB pretreated in hydrothermal system followed by autoclaving, respectively. From these values, it was decided to use autoclaved BCA as a substrate for optimization of hydrogen and organic acids productions from the design methodologies of the central compound and response surface. Ten batch reactors (R1 to R10) were monitored in triplicates with different substrate concentrations (0.8 to 9.2 g/L) and pH (4.6 to 7.4). The highest production of hydrogen (24.06 mmol/L) and 6.42 g/L of organic acids were obtained in R4 (8.0 g BCA/L and pH 7.0). Glucose, arabinose, xylose, mannose and galactose were produced and consumed throughout the operating time of all reactors, and arabinose was observed at higher concentration, 1,415.26 and 1,372.45 mg/L in R3 (8.0 g BCA/L and pH 5.0) and R8 (5.0 g BCA/L and pH 7.4), respectively. The production of hydrogen was concomitant to the formation of organic acids, mainly butyric (from 14.6 to 33.8% in R1 and R6, respectively) and succinic (from 19.5 to 26.4% in R3 and R9, respectively). The two factors analyzed, substrate concentration and pH, had significant effects on the production of hydrogen, butyric acid and succinic acid. From the results obtained with the factorial design, it was possible to verify that the maximum value of hydrogen production estimated by the model was 23.10 mmol/L, to 7.0 g BCA L and pH 7.2. The value obtained in the optimization experiment (Rotm) was 19.84 mmol/L, with an accuracy of 85.9% for hydrogen production from autoclaved BCA. Sequencing by the Illumina platform (Miseq) was performed for the identification of bacteria from the central point reactor (R9, 5.0 g BCA/L and pH 6.0), optimized reactor (Rotm, 7.0 g BCA/L and pH 7.2), autoclaved BCA and inoculum samples. In the inoculum were identified mainly bacteria similar to Clostridium bifermentans (62,69% of relative abundance), Bacillus coagulans (31,67%) and Enterobacter aerogenes (2,72%). Bacteria similar to C. bifermentans (31.91%), C. cellobioparum (32.29%), C. cellulolyticum (5.69%), C. sartagoforme (14.63%) and Paenibacillus spp. (11.67%). These bacteria were not favored under the conditions imposed on R9 (5.0 g BCA/L and pH 6.0) and Rotm (7.0 g BCA/L and pH 7.2), since the relative abundance of the bacteria in the reactor samples were completely different. In R9, bacteria similar to Lactobacillus paracasei and Escherichia hermannii were the main identified with 37.50 and 34.32% of relative abundance, respectively. In Rotm, the main bacteria identified were similar to Bacteroides sp. and Enterobacter aerogenes, with 37.35 and 27.72% relative abundance, respectively. Thus, bacterial populations, as well as the production of metabolites, were altered as a function of the imposed conditions; ie, BCA concentration, pH in batch reactors with autoclaved BCA as substrate.
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35

Myburgh, Jacolene. "A pharmacokinetic-pharmacodynamic relationship study between GABA-ergic drugs and anxiety levels in an animal model of PTSD / Jacolene Myburgh." Thesis, North-West University, 2005. http://hdl.handle.net/10394/1320.

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36

Caxias, Junior Osiris Antunes de. "Efeito adicional do butirato de sódio na alimentação de leitões." Universidade Estadual do Oeste do Paraná, 2016. http://tede.unioeste.br:8080/tede/handle/tede/1591.

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Made available in DSpace on 2017-07-10T17:48:13Z (GMT). No. of bitstreams: 1 Osiris_Antunes_Caxias_Junior.pdf: 679064 bytes, checksum: 852e69e55b04ad44a7dbe0c22c5025e2 (MD5) Previous issue date: 2016-03-11<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This study aimed to evaluate the performance, the incidence of diarrhea and rectal microbiological profile in piglets in nursery phase fed diets with and without the addition of sodium butyrate 30% coated. For that, 80 crossbred commercial barrows and gilts were used, with average weight of 9.47 (1.03) kg, in a randomized complete block design with four treatments repeated twice in both blocks, and five pigs of same sex by each experimental unit. Treatments consisted in a combination of two experimental diets with and without inclusion of sodium butyrate coated as a supplementary product to the diet, and both sexes. The experimental diets were based on corn and soybean meal and were added or not 0.1% of sodium butyrate 30% coated to the diets from diet pre-initial I. The final body weight, daily weight gain, daily feed intake and feed conversion were evaluated. There was no significant effect of product tested on animal performance. There was a significant effect (p=0.05) of sodium butyrate in the incidence of diarrhea, where pigs fed diets containing sodium butyrate had lower rates of diarrhea than pigs who did not receive the product. Rectal microbiological profile was determined by quantitative analysis of Escherichia coli, Clostridium sulfite reducers and lactic acid bacteria having reduced count of E. coli from 14th to 28th day but no effect on other microorganisms evaluated. The blood parameters measured in two animals of each experimental unit have been within the normal physiological parameters of the species. The addition of sodium butyrate coated 30% did not affect the performance of piglets in nursery phase in experimental environment with reduced health challenges, however, it was effective in reducing diarrhea-causing gastrointestinal disorders<br>Este trabalho teve por objetivo avaliar o desempenho, a incidência de diarreia e o perfil microbiológico retal em leitões na fase de creche alimentados com dietas com e sem a adição de butirato de sódio 30% revestido. Foram utilizados 80 leitões, machos e fêmeas mestiços de linhagem comercial, com peso médio inicial de 9,47 (1,03) kg, em delineamento experimental de blocos casualizados com quatro tratamentos repetidos duas vezes nos dois blocos, e com cinco suínos de mesmo sexo por unidade experimental. Os tratamentos foram constituídos pela combinação de duas rações experimentais, com e sem inclusão do butirato de sódio revestido como produto suplementar à dieta, e dois sexos. As rações experimentais, à base de milho e farelo de soja, foram acrescidas ou não de 0,1% do butirato de sódio 30% revestido a partir da dieta pré-inicial I. Foram avaliados o peso corporal final, ganho de peso diário, consumo diário de ração e conversão alimentar. Não houve efeito significativo do produto testado sobre o desempenho dos animais. Houve efeito (p=0,05) do butirato de sódio na incidência de diarreia, em que suínos alimentados com dietas contendo o butirato de sódio apresentaram menores índices de diarreia do que os suínos que não receberam o produto. O perfil microbiológico retal foi determinado com análises quantitativas de Escherichia coli, Clostridium sulfito redutores e bactérias ácido-láticas apresentando redução da contagem de E. coli do 14° ao 28° dia, mas sem efeitos para os outros micro-organismos avaliados. Os parâmetros sanguíneos, mensurados em dois animais de cada unidade experimental, apresentaram-se dentro dos parâmetros fisiológicos normais da espécie. A inclusão do butirato de sódio 30% revestido não alterou o desempenho de leitões na fase de creche em ambiente experimental com reduzidos desafios sanitários, entretanto, foi eficiente na redução de distúrbios gastrointestinais causadores de diarreia
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37

Andrade, Fábia de Oliveira. "Efeitos da associação entre vitamina A e ácido butírico em células de adenocarcinoma mamário humano da linhagem MCF-7." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/9/9132/tde-15072011-103734/.

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O câncer de mama é a principal causa de morte por neoplasias em mulheres no mundo. Nutrientes, como vitamina A (VA) e ácido butírico (AB) podem modular a carcinogênese por meio de mecanismos epigenéticos, como acetilação de histonas e metilação do DNA. A associação de agentes desmetilantes do DNA e inibidores de desacetilases de histonas representa estratégia promissora para controle do câncer, inclusive de mama. Este trabalho teve como objetivo avaliar os efeitos da administração de vitamina A e ácido butírico, isolados ou em associação, em células de adenocarcinoma mamário humano da linhagem MCF-7. Para tanto, em células MCF-7, tratadas com VA (10 &#181;M) e/ou AB (1mM) durante diferentes períodos, foram avaliados: crescimento celular, padrão de acetilação de histonas e de metilação global do DNA; expressão dos genes RAR&#946; e CRBP-I, padrão de metilação da região promotora do gene RAR&#946; e concentração celular de retinóides. Em comparação ao controle, representado por células MCF-7 não tratadas com as substâncias, o tratamento com VA e AB associados, mas não isolados, resultou em inibição significativa do crescimento de células MCF-7 (p>0,05) após período de 120hs. Nesse caso, observaram-se inibições do crescimento de 10%, 34% e 46% para os tratamentos com VA, AB e VA+AB, respectivamente. Em comparação ao controle, AB e associação de VA+AB, mas não VA isolada, aumentaram (p<0,05) o nível de acetilação de H3K9, mas não de H4K16, após 96hs de tratamento, não se verificando diferenças (p>0,05) entre os tratamentos com AB e VA+AB. VA e AB, isolados ou em associação, não alteraram (p>0,05) o padrão de metilação global do DNA e nem a expressão do gene CRBP-I, em comparação ao controle. AB e associação de VA+AB, mas não VA isolada, aumentaram (p<0,05) a expressão do gene RAR&#946; após 120hs de tratamento, em comparação ao controle, não se verificando diferenças (p>0,05) entre os tratamentos com AB e VA+AB. Células MCF-7 tratadas ou não com VA e AB, isolados ou em associação, apresentaram promotor do gene RAR&#946; predominantemente metilado e níveis não detectáveis de palmitato de retinila. Em comparação ao controle, apenas o tratamento com VA isolada aumentou (p<0,05) da concentração de retinol após 120hs. Com base nos resultados, a associação de VA e AB resultou em efeito inibitório aditivo do crescimento de células MCF-7. Acetilação de histonas H3K9, mas não de H4K16 e metilação do DNA, parece representar alvo epigenético do AB. Aumento da expressão do gene supressor de tumor RAR&#946; parece estar envolvido na inibição do crescimento de células MCF-7 pelo AB. O gene CRBP-I não parece estar envolvido na inibição do crescimento de células MCF-7 pela VA e AB, isolados ou em associação. Ausência de esterificação do retinol em células MCF-7 tratadas ou não com VA e AB, isolados ou em associação, parece se relacionar à expressão reduzida do gene CRBP-1.<br>Breast cancer is the leading cause of deaths among women diagnosed with neoplasia worldwide. Nutrients such as vitamin A (VA) and butyric acid (BA) may modulate carcinogenesis through epigenetic mechanisms, such as histone acetylation and DNA methylation. The combination of DNA demethylating agents and histone deacetylase inhibitors represent a promising strategy for cancer control, including breast cancer. This study aimed to evaluate the effects of administration of vitamin A and butyric acid, isolated or combined, on MCF-7 human breast adenocarcinoma cell line. For this, the following parameters were evaluated in MCF-7 cells treated for different periods with VA (10 &#181;M) and/or BA (1 mM): cell growth, histone acetylation status, global DNA methylation pattern, RAR&#946; and CRBP-I gene expression, RAR&#946; promoter methylation status, and cellular concentration of retinoids. Compared to controls, represented by untreated MCF-7 cells, treatment with VA and BA combined, but not isolated, significantly (p<0.05) inhibited the growth of MCF-7 cells after 120hs. In this case, 10%, 34% and 46% growth inhibitions were observed after treatment with VA, BA and VA+BA, respectively. Compared to controls, BA and its association with VA, but not VA isolated, increased (p<0.05) acetylation level of H3K9, but not of H4K16, after 96hs; no differences were observed between treatments with BA and VA+BA. VA and BA, isolated or combined, did not alter (p>0.05) global DNA methylation pattern and CRBP-I gene expression, compared to controls. BA and its association with VA, but not VA isolated, increased RAR&#946; gene expression after 120hs, compared to controls; no differences were observed between treatments with BA and VA+BA. MCF-7 cells, treated or not with VA and BA, isolated or combined, presented RAR&#946; promoter predominantly methylated and undetectable levels of retinyl palmitate. Compared to controls, only treatment with VA isolated increased (p<0.05) cellular retinol concentration after 120hs. Based on these data, association between VA and BA resulted in additive inhibitory effect on MCF-7 cell growth. Acetylation of H3K9, but not of H4K16, seems to represent a BA epigenetic target. Increased expression of tumor suppressor gene RAR&#946; seems to be involved in BA inhibitory action on MCF-7 cell growth. Neither CRBP-I gene nor global DNA methylation seem to be involved in VA and/or BA inhibitory actions on MCF-7 cell growth. Lack of retinol esterification in MCF-7 cells treated or not with VA and BA, isolated or combined, could be related to reduced CRBP-I gene expression.
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38

Tripathy, Srikant. "Interactions between GABAergic, dopaminergic and cholinergic neurotransmitter systems in form deprived myopic chick." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/18385/1/Srikant_Tripathy_Thesis.pdf.

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Myopia is a refractive defect of the eye in which collimated light produces images focused in front of the retina. Myopia can be artificially induced in animal models by form deprivation (form deprivation myopia, FDM) or by application of negative lenses (lens induced myopia, LIM). In this study myopia was induced using diffusers. The project had two main aims: 1. To determine if there is an interaction between the GABAergic system and dopaminergic system in the retina in terms of myopia? 2. To determine if there is an interaction between the GABAergic system and cholinergic system in the retina in terms of myopia? Firstly, an experiment focusing on the interaction between dopaminergic receptors antagonists and GABAC receptor antagonist was developed. Comparison of the different drug treated eye with the control was found and the effects of combination injections were compared to individual drug injections. Use of different blockers for various subtype of receptors simplified the understandings the underlying pharmacological interventions for GABAC receptor antagonist TPMPA. The D1 subtype of receptors was found to be involved in transmission of signals from GABAC receptors. Our results showed that D1 receptor antagonist SCH-23390 antagonizes the actions of TPMPA. In addition to this it was also found that possibly 5HT receptor may also play an important role in modulation of signaling from GABA receptor to dopaminergic receptors in the retina. These results were consistent with the drug combination effects for agonists. GABA A/C receptor agonist muscimol negativate the efficacy of D1 receptor agonist SKF-38393 but the activity of D2/4 receptor agonist quinpirole was not affected by muscimol. Although dopaminergic receptors are found to interact with GABAergic signaling, but an alternative interaction with anticholinergic (most widely studied antimyopic agents) could not be ruled out. This problem led to a follow-up experiment, in which GABA receptors intervention in anticholinergic agents was studied. The GABAergic receptor agonist muscimol when injected with anticholinergics (atropine and pirenzepine) showed a moderate interaction. As muscimol interacted with atropine to a lesser extent a more specific M1/5 receptor antagonist pirenzepine (earlier found to inhibit myopia) was used under these circumstances. The second aim to study the interaction between muscimol and pirenzepine showed more interaction with GABAA/C receptor agonist. There were data suggesting that there is a muscarinic and GABAergic interaction in retina, such that each modulation of each receptor had an effect on FDM. However, a drug combination treatment helped in understanding the underlying mechanism. Several previous studies have indicated that there exist a strong interaction between excitatory neurotransmitter acetylcholine and inhibitory transmitter GABA in retina. The results of this study indicate a similar finding. Thus results of this study may be summarized as: 1. D1 antagonists and not D2 antagonists blocks the antimyopic effects of GABAC antagonist TPMPA 2. GABA A/C agonist muscimol partially blocks the antimyopic activity of anticholinergics (e.g. atropine and pirenzepine).
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39

Tripathy, Srikant. "Interactions between GABAergic, dopaminergic and cholinergic neurotransmitter systems in form deprived myopic chick." Queensland University of Technology, 2008. http://eprints.qut.edu.au/18385/.

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Abstract:
Myopia is a refractive defect of the eye in which collimated light produces images focused in front of the retina. Myopia can be artificially induced in animal models by form deprivation (form deprivation myopia, FDM) or by application of negative lenses (lens induced myopia, LIM). In this study myopia was induced using diffusers. The project had two main aims: 1. To determine if there is an interaction between the GABAergic system and dopaminergic system in the retina in terms of myopia? 2. To determine if there is an interaction between the GABAergic system and cholinergic system in the retina in terms of myopia? Firstly, an experiment focusing on the interaction between dopaminergic receptors antagonists and GABAC receptor antagonist was developed. Comparison of the different drug treated eye with the control was found and the effects of combination injections were compared to individual drug injections. Use of different blockers for various subtype of receptors simplified the understandings the underlying pharmacological interventions for GABAC receptor antagonist TPMPA. The D1 subtype of receptors was found to be involved in transmission of signals from GABAC receptors. Our results showed that D1 receptor antagonist SCH-23390 antagonizes the actions of TPMPA. In addition to this it was also found that possibly 5HT receptor may also play an important role in modulation of signaling from GABA receptor to dopaminergic receptors in the retina. These results were consistent with the drug combination effects for agonists. GABA A/C receptor agonist muscimol negativate the efficacy of D1 receptor agonist SKF-38393 but the activity of D2/4 receptor agonist quinpirole was not affected by muscimol. Although dopaminergic receptors are found to interact with GABAergic signaling, but an alternative interaction with anticholinergic (most widely studied antimyopic agents) could not be ruled out. This problem led to a follow-up experiment, in which GABA receptors intervention in anticholinergic agents was studied. The GABAergic receptor agonist muscimol when injected with anticholinergics (atropine and pirenzepine) showed a moderate interaction. As muscimol interacted with atropine to a lesser extent a more specific M1/5 receptor antagonist pirenzepine (earlier found to inhibit myopia) was used under these circumstances. The second aim to study the interaction between muscimol and pirenzepine showed more interaction with GABAA/C receptor agonist. There were data suggesting that there is a muscarinic and GABAergic interaction in retina, such that each modulation of each receptor had an effect on FDM. However, a drug combination treatment helped in understanding the underlying mechanism. Several previous studies have indicated that there exist a strong interaction between excitatory neurotransmitter acetylcholine and inhibitory transmitter GABA in retina. The results of this study indicate a similar finding. Thus results of this study may be summarized as: 1. D1 antagonists and not D2 antagonists blocks the antimyopic effects of GABAC antagonist TPMPA 2. GABA A/C agonist muscimol partially blocks the antimyopic activity of anticholinergics (e.g. atropine and pirenzepine).
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40

Christian, Parul. "GABAergic modification of myopic and hyperopic ocular tissue effects on scleral fibroblast growth." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/54639/1/Parul_Christian_Thesis.pdf.

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Purpose: Myopia is a common eye disorder affecting up to 90% of children in South East Asia and 30% of the population worldwide. Myopia of high severity is a leading cause of blindness around the world (4th to 5th most common). Changes and remodelling of the sclera i.e. increase cellular proliferation & increase protein synthesis within scleral cells (↑ scleral DNA) and thinning and lose of extracellular matrix of sclera (↓ scleral GAG synthesis) have been linked to myopic eye growth in animal models. Signals acting on the sclera are thought to originate in the retina, and are modulated by the retinal pigment epithelium (RPE) with limited evidence suggesting that the RPE can modify scleral cell growth in culture. However, the mechanism of retinal signal transmission and the role of posterior eye cup tissue, including the RPE, in mediating changes in scleral fibroblast growth during myopia development are unclear. Retinal transmitter systems are critically involved in pathways regulating eye growth, which ultimately lead to alterations in the sclera if eye size is to change. A dopaminergic agonist and muscarinic antagonists decrease the proliferation of scleral chondrocytes when co-cultured with chick’s retinal pigment epithelium (RPE). GABA receptors have recently been localised to chick sclera. We therefore hypothesised that posterior eye cup tissue from myopic eyes would stimulate and from hyperopic eyes would inhibit growth of scleral fibroblasts in vitro and that GABAergic agents could directly interact with scleral cells or indirectly modify the effects of myopic and hyperopic posterior eye cup tissue on scleral fibroblast growth. Method: Fibroblastic cells obtained from 8-day-old chick sclera were used to establish cell banks. Two major experiments were performed. Experiment 1: To determine if posterior eye cup tissues from myopic eye stimulates and hyperopic eye inhibits scleral cell proliferation, when co-cultured with scleral cells in vitro. This study comprised two linked experiments, i) monocular visual treatments of FDM (form-deprivation myopia), LIM (lens-induced myopia) and LIH (lens-induced hyperopia) with assessment of the effect of full punch eye cup tissue on DNA and GAG synthesis by cultured chick scleral fibroblasts, and ii) binocular visual treatments comprising LIM and LIH with assessment of the effect of individual layers of eye cup tissues (neural retina, RPE and choroid) on cultured chick scleral fibroblasts. Visual treatment was applied for 3 days. Experiment 2: To determine the direct interaction of GABA agents on scleral cell growth and to establish whether GABA agents modify the stimulatory/inhibitory effect of myopic and hyperopic posterior eye cup tissues on cultured scleral cell growth in vitro. Two linked experiments were performed. i) GABA agonists (muscimol and baclofen) and GABA antagonists (bicuculine (-), CGP46381 and TPMPA) were added to scleral cell culture medium to determine their direct effect on scleral cells. ii) GABAergic agents (agonists and antagonists) were administered to scleral fibroblasts co-cultured with posterior eye cup tissue (retina, RPE, retina/RPE, RPE/choroid). Ocular tissues were obtained from chick eyes wearing +15D (LIH) or -15D lenses (LIM) for 3 days. In both experiments, tissues were added to hanging cell culture insert (pore size 1.0ìm) placed over each well of 24 well plates while scleral cells were cultured in DMEM/F12, Glutamax (Gibco) plus 10% FBS and penicillin/streptomycin (50U/ml)) and fungizone (1.25ug/ml) (Gibco), at seeding density of 30,000 cells/well at the bottom of the well and allowed to grow for 3 days. Scleral cells proliferation rate throughout the study was evaluated by determining GAG and DNA content of scleral cells using Dimethylmethylene blue (DMMB) dye and Quant-iTTm Pico Green® dsDNA reagent respectively. Results and analysis: Based on DNA and GAG content, there was no significant difference in tissue effect of LIM and LIH eyes on scleral fibroblast growth (DNA: 8.4 ± 1.1μg versus 9.3 ± 2.3 μg, p=0.23; GAG: 10.13 ± 1.4 μg versus 12.67 ± 1.2 μg, F2,23=6.16, p=0.0005) when tissues were obtained from monocularly treated chick eyes (FDM or +15D lens or -15D lens over right eyes with left eyes untreated) and co-cultured as full punch. When chick eyes were treated binocularly with -15D lens (LIM) right eye and +15D lens (LIH) left eyes and tissue layers were separated, the retina from LIM eyes did not stimulate scleral cell proliferation compared to LIH eyes (DNA: 27.2 ± 6.7 μg versus 23.2 ± 1.5 μg, p=0.23; GAG: 28.1 ±3.7 μg versus 28.7 ± 4.2 μg, p=0.21). Similarly, the LIH and LIM choroid did not produce a differential effect based on DNA (LIM 46.9 ± 6.4 μg versus LIH 53.5 ± 4.7 μg, p=0.18), however the choroid from LIH eyes induced higher scleral GAG content than from LIM eyes (32.5 ± 6.7 μg versus 18.9 ± 1.2 μg, p=0.023). In contrast, the RPE from LIM eyes caused a significant increase in fibroblast proliferation whereas the RPE from LIH eyes was relatively inhibitory (72.4 ± 6.3 μg versus 27.9 ± 2.3 μg, F1, 6=69.99, p=0.0005). GAG data were opposite to DNA data e.g. the RPE from LIH eyes increased (33.7 ± 7.9 μg) while the RPE from LIM eyes decreased (28.2 ± 3.0 μg) scleral cell growth (F1, 6=13.99, p=0.010). Based on DNA content, GABA agents had a small direct effect on scleral cell growth; GABA agonists increased (21.4 ± 1.0% and 18.3 ± 1.0% with muscimol and baclofen, p=0.0021), whereas GABA antagonists decreased fibroblast proliferation (-23.7 ± 0.9% with bicuculine & CGP46381 and -28.1 ± 0.5% with TPMPA, p=0.0004). GABA agents also modified the effect of LIM and LIH tissues (p=0.0005).The increase in proliferation rate of scleral fibroblasts co-cultured with tissues (RPE, retina, RPE/retina and RPE/choroid) from LIM treated eyes was enhanced by GABA agonists (muscimol: 27.4 ± 1.2%, 35.8 ± 1.6%, 8.4 ± 0.3% and 11.9 ± 0.6%; baclofen: 27.0 ± 1.0%, 15.8 ± 1.5%, 16.8 ± 1.2% and 15.4 ± 0.4%, p=0.014) whereas GABA antagonists further reduced scleral fibroblasts growth (bicuculine: -52.5 ± 2.5%, -36.9 ± 1.4%, -37.5 ± 0.6% and -53.7 ± 0.9%; TPMPA: 57.3 ± 1.3%, -15.7 ± 1.2%, -33.5 ± 0.4% and -45.9 ± 1.5%; CGP46381: -51.9 ± 1.6%, -28.5 ± 1.5%, -25.4 ± 2.0% and -45.5 ± 1.9% respectively, p=0.0034). GAG data were opposite to DNA data throughout the experiment e.g. GABA agonists further inhibited while antagonists relatively enhanced scleral fibroblasts growth for both LIM and LIH tissue co-culture. The effect of GABA agents was relatively lower (p=0.0004) for tissue from LIH versus LIM eyes but was in a similar direction. There was a significant drug effect on all four tissue types e.g. RPE, retina, RPE/retina and RPE/choroid for both LIM and LIH tissue co-culture (F20,92=3.928, p=0.0005). However, the effect of GABA agents was greatest in co-culture with RPE tissue (F18,36=4.865, p=0.0005). Summary and Conclusion: 1) Retinal defocus signals are transferred to RPE and choroid which then exert their modifying effect on scleral GAG and DNA synthesis either through growth stimulating factors or directly interacting with scleral cells in process of scleral remodeling during LIM and LIH visual conditions. 2) GABAergic agents affect the proliferation of scleral fibroblasts both directly and when co-cultured with ocular tissues in vitro.
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41

Silveira, Ronilda Terezinha. "POTENCIAL DE APLICAÇÃO DE MARCADORES RAPD E DE ENRAIZAMENTO DE ESTACAS E MINIESTACAS DE CLONES DE ERVA-MATE." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/8713.

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The rescue of selected adult plants and the renewing of explants constitute the greatest challenge to enable the clonal propagation of mate (Ilex paraguariensis St. Hil.). The objectives of this study were to identify and separate clones of the clonal garden by RAPD markers and to evaluate the effect of different doses of indol butyric acid (IBA) on rooting of cuttings and minicuttings of different clones of mate. Three experiments were carried out. The first, young leaves of ten clones had the DNA extracted for testing RAPD markers. The second, new shoots of stump of four clones were used to set up one bud cuttings with one half leaf. The third experiment, rooted cuttings of 20 year-old-trees were used to set up a clonal minigarden to collect minicuttings of one bud and one half leaf. All cuttings and minicuttings were treated with different doses of IBA. The RAPD technique is successful for clone separation and identification, being the primers OPP-03, OPP-06, OPP-15 and OPP-16 the most polymorphic. Single bud cuttings of new sprouts from stumps of some mate clones are capable of rooting, without the need of indole butyric acid. The clones FO10 and FO52 have different capability for rooting. Minicuttings of the clone FO10 root without indol butyric acid.<br>O resgate de plantas adultas selecionadas e o rejuvenescimento dos propágulos se constituem no maior desafio para viabilizar a clonagem massal da erva-mate (Ilex paraguariensis St. Hil.). Os objetivos deste trabalho foram identificar e separar clones que compõem o jardim clonal por meio de marcadores RAPD e avaliar o efeito de diferentes doses de ácido indol butírico (AIB) no enraizamento de estacas e miniestacas de diferentes clones de erva-mate. Para tanto foram realizados três experimentos. No primeiro, folhas jovens de dez clones tiveram o DNA extraído para testar marcadores RAPD. No segundo, brotações de cepas de quatro clones foram utilizadas para preparar estacas de gema única, com folha cortada pela metade. No terceiro experimento, estacas enraizadas de árvores com 20 anos de idade foram utilizadas para a formação de um minijardim clonal e produção de miniestacas com gema única e uma folha cortada pela metade. Para o enraizamento, tanto as estacas quanto as miniestacas foram tratadas com diferentes doses de AIB. A técnica RAPD é eficaz para a separação de clones de erva-mate, sendo que os iniciadores OPP-03, OPP-06, OPP-15 e OPP-16 foram os mais polimórficos. Estacas de gema única de brotações oriundas da decepa de alguns clones de erva-mate são competentes para o enraizamento, o que dispensa o uso de ácido indol butírico. Os clones FO10 e FO52 diferem quanto a competência ao enraizamento das miniestacas. O enraizamento de miniestacas do clone FO10 ocorre sem a aplicação de ácido indol butírico.
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42

Leite, Marcondes Lopes. "Propagação assexuada de fruteiras da família clusiacea (Platonia insignis Mart.) e bacuparizeiro (Garcinia gardneriana (Planch & Triana) Zappi)." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154526.

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Submitted by Marcondes Lopes Leite (marcondesleite@ifma.edu.br) on 2018-07-17T03:02:40Z No. of bitstreams: 1 DISSERTAÇÃO_Marcondes (1).pdf: 855505 bytes, checksum: 87f199a0b3c25e7ac6c9ca3496aaff6b (MD5)<br>Approved for entry into archive by Karina Gimenes Fernandes null (karinagi@fcav.unesp.br) on 2018-07-17T11:51:19Z (GMT) No. of bitstreams: 1 leite_ml_me.pdf: 825599 bytes, checksum: 98eaa2d4a84e378b555cde009287328e (MD5)<br>Made available in DSpace on 2018-07-17T11:51:19Z (GMT). No. of bitstreams: 1 leite_ml_me.pdf: 825599 bytes, checksum: 98eaa2d4a84e378b555cde009287328e (MD5) Previous issue date: 2018-05-30<br>Outra<br>PROPAGAÇÃO ASSEXUADA DE FRUTEIRAS DA FAMILIA CLUSIACEA: BACURIZEIRO (Platonia insignis Mart.) E BACUPARIZEIRO (Garcinia gardneriana (Planch & Triana) Zappi). RESUMO As fruteiras bacuri (Platonia insignis Mart.) e bacupari (Garcinia gardneriana (Planch & Triana) Zappi).pertencem à família Clusiaceae e predominam no Norte do Brasil. Estas espécies não são domesticadas e a obtenção de frutos é feita principalmente por meios extrativos sendo raros pomares comerciais. Para à propagação por estaquia do bacurizeiro, ramos jovens foram retirados de uma planta matriz e as estacas foram obtidas como: i. estacas lenhosas, ii. estacas herbáceas com duas folhas e duas gemas na base e iii. estacas herbáceas com duas folhas, sem gemas na base. As estacas foram tratadas com ácido indol butírico (AIB) nas seguintes concentrações: 0.0 (controle), 1.000, 2.000, 3.000 e 4.000 mg.L-1. As estacas lenhosas apresentaram a maior taxa de sobrevivência (95,83%) em relação as estacas herbáceas (70 e 67,5%), sendo que em apenas uma dessas foi observado o desenvolvimento radicular (0,28%). Em relação ao bacuparizeiro, como o estiolamento tem sido utilizado para melhorar o enraizamento em espécies de difícil propagação e como não foram encontrados relatos sobre o uso de estacas estioladas para propagar esta espécie, o objetivo deste estudo foi avaliar a viabilidade dessa técnica de propagação e estudar o efeito de diferentes doses de AIB. As estacas estioladas continham um par de folhas (~12 cm de comprimento) e foram tratadas com AIB por 10 segundos (0 – controle, 500, 1.000 e 2.000 mg.L-1). O estiolamento resultou em 2,5% de estacas enraizadas quando tratadas com 500 e 1.000 mg.L-1 de AIB. O tratamento com IBA afetou a sobrevivência das estacas na fase de propagação, possivelmente ao reduzir a retenção foliar quando estas foram tratadas com concentrações de IBA superiores a 1.000 mg.L-1. Os experimentos foram realizados no outono-inverno, estes devem ser repetidos na primavera-verão, pois espécies neotropicais requerem clima quente e úmido para seu desenvolvimento.<br>Bacuri (Platonia insignis Mart.) and bacupari (Garcinia gardneriana (Planch & Triana) Zappi.) fruit trees belong to the Clusiaceae family and they predominate in the North of Brazil in the Amazonia basin. These species are not domesticated and fruit are obtained mainly by extractive means due to the inexistence of commercial orchards. To propagate bacuri by cutting, young branches were taken from an matrix bacuri tree and cuttings were obtained as: i. hardwood cuttings, ii. herbaceous stem cuttings with two leaves and two buds on the base, and iii. herbaceous stem cuttings with two leaves without buds on the base. Cuttings were treated with indolbutyric acid (IBA) in the following concentrations: 0,0 mg.L-1 (control), 1,000 mg.L-1 , 2,000 mg.L-1 , 3,000 mg.L-1 , and 4,000 mg.L-1 . The hardwood cuttings presented the biggest survival rate (95.83%) in relation to the herbaceous stem cuttings (70%, 67.50%), and in only one of this cutting was observed root development (0.28%). Regarding bacupari, as etiolation has been used to improve rooting in species which are difficult to propagate and as there is no reports regarding the use of etiolate cuttings to propagate this species, the objective of this study was to evaluate the feasibility of this technique to propagate bacupari and to study the effect of the different doses of IBA. Etiolate cuttings contained on pair of leaves (~12 cm long), and were treated with IBA for 10 seconds (0,0-control, 500, 1,000, and 2,000 mg.L-1 ). Etiolation resulted in 2.5% rooted cuttings when treated with 500 and 1,000 mg.L-1 IBA. The IBA treatment affected the cuttings surviving the propagate phase possibly by reducing the foliar retention when treated with IBA concentrations superior than 1,000 mg.L-1 . The experiments were set during the autumn-winter season, they should be repeated in the spring-summer season as these species require hot and humid climate to develop.
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43

Fürll, Manfred. "Vorkommen, Ätiologie, Pathogenese, Diagnostik und medikamentelle Beeinflussung von Leberschäden beim Rind." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-89026.

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Aufgabenstellung Bei Milchkühen wird häufig in Verbindung mit Leistungsminderung und Gesundheits-störungen von einer Überlastung der Leber gesprochen. Makroskopisch sichtbare Veränderungen dieses Organes bei Not-, Krank-, aber auch bei Normalschlachtun-gen scheinen diese Meinung zu unterstützen. Da sich z.B. von 1950 mit 1851 kg bis 1985 mit 4370 kg (3,5% Fett) die durchschnittliche Jahresmilchleistung der Kühe in der DDR mehr als verdoppelte, Stammkühe sogar 7255 kg erreichten, wird aus die-ser Leistungsentwicklung und den damit verbundenen Anforderungen z. T. unkritisch schnell auf ein Leberversagen geschlossen, besonders dann, wenn zusätzliche Qua-litätsmängel des Futters vorliegen. Eine klinische Objektivierung des Leberzustandes wird allgemein für schwierig und die therapeutische Beeinflussbarkeit für wenig aus-sichtsreich gehalten. Aus dieser Situation wurde die Aufgabe abgeleitet, - das gegenwärtige Vorkommen von Leberschäden beim Rind zu erfassen und zu analysieren - die Bedeutung des Buttersäureeinflusses, der peripartalen Fütterung, eines Fut-terentzuges sowie einer medikamentell stimulierten Lipolyse für die Entstehung von Leberschäden und die Entwicklung pathologischer Prozesse zu untersuchen - die Diagnostik von Leberschäden bei Berücksichtigung von Belangen der tierärzt-lichen Praxis zu objektivieren und - Möglichkeiten zur medikamentellen Entlastung der Leber sowie ausgewählter Präparate auf leberschädigende Effekte zu prüfen Bei der Bearbeitung bildeten die Lipidansammlung als die häufigste Schädigungsart der Leber sowie die freien Fettsäuren (FFS) im Blut und ihre Beziehung zu Kriterien der Leberfunktion den Schwerpunkt. Material und Methodik Das Vorkommen von Leberschäden wurde analysiert in - 2 Milchproduktionsbetrieben (A und B) an 22 bzw. 18 SMR-Kühen mit einer Jah-resmilchleistung von 4500 bzw. 5350 kg FCM im peripartalen Zeitraum - während 5-jähriger Stoffwechselkontrollen nach TGL 34313 in einem Bezirk bei Kühen 2 bis 8 Wochen p. p. mit einem Leistungsniveau zwischen 3500 bis 5000 kg FCM - an 336 Rindern einer Medizinischen Tierklinik in den Jahren 1978 bis 1987 - an 941 not- und krankgeschlachteten Rindern (895 Kühe, 46 Mastbullen) zweier Sanitätsschlachtbetriebe (SSB A und B) mit klinisch-chemischen (hpts. Bilirubin und ASAT im Blut sowie Leberlipide) und z. T. histologischen Methoden. Zur Ätiologie und Pathogenese von Leberschäden erfolgten Untersuchungen bei - subakuter intraruminaler Buttersäurebelastung (0,5-, 1,0-,2,0 g/kg KM) an 42 Rin-dern - 95 Kühen im peripartalen Zeitraum mit unterschiedlicher Fütterung, und zwar • energiereich in der Trockenperiode (a. p.), bedarfsgerecht p. p. • energiereich a. p., energiereduziert p. p. • energiereduziert ab 4 bis 2 Wochen a. p., bedarfsgerecht p. p. • nach den Angaben des DDR-Futtermittelbewertungssystemes - 10 Kühen und Schafen während 3-, 10- und 12-tägigen Futterentzuges sowie bei - Intravenöser Adrenalinapplikation (3 Kühe, 0,5 mg/100 kg KM) durch komplexe klinisch-chemische und histologische Analysen mit den Schwerpunk-ten Leberlipide sowie FFS, Bilirubin, ASAT, Ketonkörper und Glucose im Blut unter Einbeziehung weiterer Kriterien des Kohlenhydrat-, Fett-, Eiweiß- und Mineralstoff-wechsels, des Säure-Base-Haushaltes sowie von Hormonen. Die Diagnostik von Leberschäden wurde bearbeitet durch - methodische Untersuchungen zum Tagesverlauf der FFS sowie zum Einfluss ei-ner Adrenalinapplikation (9 bzw. 6 Rinder) - Vergleich zwischen indirekter (Leberschwimmprobe) und direkter Leberlipid-bestimmung (59 Kühe) - Analyse verschiedener Leberfunktions- und Stoffwechselparameter im periparta-len Zeitraum (40 Kühe) - Analyse der Befunde von 101 not- und krankgeschlachteten Kühen. In den Mittelpunkt wurden dabei die Leberlipide und die diagnostische Aussagefä-higkeit der FFS in Beziehung zu weiteren klinisch-chemischen sowie histologischen Parametern gestellt. Eine leberentlastende Wirkung wurde für Nicotinsäure an 20 Kühen bei 3 Tagen Futterentzug (5 und 10 g/d) sowie an 35 Kühen peripartal 1 Wo-che a. p. und 2 Wochen p. p. bei verschiedenen Dosierungen und z. T. Energiere-striktion, für Biliton® (Dehydrocholsäure) (5,5 g/d) an 9 Kühen peripartal sowie an 5 kranken Rindern getestet. Die Prüfung möglicher leberschädigender Effekte von ACTH (0,5, 0,6 und 1,0 IE/kg KM) und Glucocorticosteroiden (Prednisolut® - 0,5 mg/kg FM; Prednisolon 0,2, 04 und 0,6 mg/kg KM) erfolgte bei ein- und fünftägiger Applikation an 10 Schafen und 26 Kühen sowie für Phenylbutazon® (5 g/d) an 5 Kü-hen peripartal. Die zum Wirkungsnachweis eingesetzten Untersuchungsmethoden umfassten komplex klinisch-chemische Kriterien, im peripartalen Zeitraum auch Leis-tungsparameter sowie z. T. histologische Befundungen. Von den erzielten Ergebnissen lassen sich folgende Thesen ableiten: Thesen 1. Leberschäden dominieren bei Kühen in der Phase der Frühlaktation und zu-sätzlich ausgangs der Winterfütterung. Ketose, Geburts- und Puerperalstörun-gen, entzündliche Prozesse und Indigestionen sind häufig von Leberschäden begleitet. Deshalb hat der Fütterung und Haltung der hochträchtigen und frischabge-kalbten Kühe, der ausgehenden Winterfütterung und der Verhütung der o. g. Krankheiten auch zur Prophylaxe von Leberschäden besondere Aufmerksam-keit zu gelten. 2. Untersuchungen in 2 Betrieben zufolge kommt die Leberverfettung bei 27% bzw. 56% der Milchkühe (4500, 5350 kg FCM) 1 bis 4 Wochen p. p. vor. Im gleichen Zeitraum liegen pathologische ASAT-Aktivitäten und Bilirubinkonzent-rationen bei 41% bzw. 56% der Kühe vor. Ihr Anteil verringert sich (21% bzw. 24%), wenn der Untersuchungszeitraum bis auf 8 Wochen p. p. ausgedehnt wird. 3. In den letzten 20 Jahren ist eine Verschiebung der Häufigkeit von Krankheiten mit Leberschäden zu beobachten. So treten hämolytische Anämien seltener auf. Fast die Hälfte der not- und krankgeschlachteten Kühe hat eine makroskopisch veränderte Leber. In ihnen überwiegt eindeutig die Leberver-fettung (55%) gegenüber reaktiv-entzündlichen (29%) und degenerativen Pro-zessen (16%). 4. Die Hauptursache gesteigerter Lipidkonzentrationen in der Leber von Milchkü-hen p. p. ist eine energetische Überfütterung in der Trockenstehperiode. Der Lipidgehalt der Leber steigt noch weiter an, wenn derartige Kühe vor der Ge-burt nicht mehr ausreichend energetisch versorgt werden. Deshalb ist der Hauptweg zur Verhütung der postpartalen Leberverfettung in der Fütterung der Milchkühe nach den Angaben des DDR-Futtermittelbewertungssystemes zu sehen. 5. Dreiwöchige Buttersäurebelastung verursacht keine Leberschädigung. Zu be-achtlicher Fettansammlung in der Leber kommt es dagegen, wenn Kühen 3 Tage das Futter entzogen wird. Die bei der Verfütterung qualitätsgeminderter Silage oft zu beobachtenden Leberschäden haben demnach nicht unmittelbar ihre Ursache in dem hohen Buttersäuregehalt, sondern sind auf andere Fakto-ren zurückzuführen, zu denen u. a. auch die energetisch unzureichende Ver-sorgung zu zählen ist. Auch im Interesse der Verhütung von Leberschäden hat der Produktion von Silagen bester Qualität alle Aufmerksamkeit zu gelten. 6. Pathogenetisch geht der postpartalen Leberverfettung ein Konzentrationsan-stieg der FFS voraus. Sie erreichen ihr Maximum 1 Woche p. p. und damit früher als die Leberlipide. Umgekehrt folgt den sinkenden FFS-Konzentrationen auch eine Abnahme der Leberlipidkonzentration. Bei Futter-entzug wird die fehlende Energieaufnahme schnell durch einen deutlichen Konzentrationsanstieg der FFS angezeigt. 7. Bei Energiemangel besteht eine gesicherte Beziehung (p ≤ 0,01) zwischen FFS und Bilirubin. Eine solche besteht auch, wenn die FFS-Konzentration durch i. v. Adrenalingaben gesteigert wurde. Dieser kausale Zusammenhang wird in der Literatur mit der Konkurrenz beider Metabolite um ein mikrosoma-les Transportprotein in den Leberzellen gedeutet. 8. In Energiemangelsituationen (postpartal, Futterentzug) treten regelmäßig stei-gende ß-OH-Butyrat (BHB)- Konzentrationen auf. Sie sind gegenüber dem Anstieg der FFS zeitlich versetzt und werden von Glucosekonzentrationen im Blutplasma bis gegen den unteren Grenzbereich als Zeichen der Kohlenhyd-ratverarmung begleitet. 9. Die Aktivität der ASAT ist postpartal durch puerperale Einflüsse (Karunkelab-bau u. a.) sowie Körpermasseverlust (Proteinabbau in Muskelzellen), nicht aber bei Futterentzug gesteigert. Die postpartal bestehenden gesicherten Be-ziehungen zwischen ASAT-Aktivität und Leberlipidkonzentration sind mittelba-rer Art. ASAT-Aktivitäten und BHB-Konzentration verlaufen nicht regelmäßig parallel. 10. Klinische Störungen gehen peripartal überwiegend mit erhöhten Leberlipid-konzentrationen einher. Keine Beziehungen bestehen zwischen Konzeptions-erfolg einerseits und den Konzentrationen der FFS und Leberlipide 1 und 2 Wochen p. p. andererseits. Bei später zuchtuntauglichen Kühen liegen die Pa-rameter Ketonkörper, Leberglycogen und die GGT im peripartalen Zeitraum gehäuft außerhalb des xˉ ± s-Bereiches. Gesichert indirekt bzw. direkt korrelie-ren die Fruchtbarkeits- und Milchleistungen mit dem Körpermasseverlust p. p.. Die individuellen Unterschiede zwischen Kühen sind beachtenswert. 11. Zur indirekten Bestimmung der Lipidkonzentration in der Leber eignet sich die Schwimmprobe. Für die Beziehung zwischen relativer Dichte (y) sowie der Lipidkonzentration (x) gilt die Beziehung y=1,095 – 0,002 x bzw. x=500(1,095-y). Die Leberschwimmprobe wird zur Anwendung in der tierärztli-chen Praxis empfohlen. Bei der Interpretation der Lipidkonzentration ist die Abhängigkeit vom Laktationsstadium zu berücksichtigen. Peripartal besteht eine gesicherte Beziehung (p ≤ 0,001) zwischen Energiedefizit und Konzentra-tion der Leberlipide. 12. Der chemisch bestimmbare Fettgehalt der Leber korreliert über eine Exponen-tialfunktion (p ≤ 0,001) mit dem histologisch in 4 bzw. 7 Klassen befundeten, jedoch liegen bei histologisch gering- und mittelgradigen Fettablagerungen i.d.R. chemisch noch keine unphysiologischen Lipidkonzentrationen vor. Die diagnostische Bedeutung der Gesamtlipidkonzentration in der Leber hängt von ihrer Genese ab und ist begrenzt. 13. Auf eine Leberverfettung kann diagnostisch mit hoher Sicherheit geschlossen werden, wenn die Konzentration der FFS, des Bilirubins und der Ketonkörper im Blut bzw. der FFS-Triglycerid-Quotient gesteigert sind. Das BHB verdient gegenüber den Gesamtketonkörpern den Vorzug, da es enger mit dem Leber-lipidgehalt korreliert. Pathologische Leberlipidkonzentrationen sind häufig, aber nicht immer mit erhöhten ASAT-Aktivitäten verbunden. 14. Bei der Interpretation der Parameter FFS, Bilirubin, Ketonkörper, ASAT und Leberlipide sind Einflüsse durch das Laktationsstadium, bei den FFS zusätz-lich durch Stress sowie bei FFS und BHB durch die Fütterung zu berücksichti-gen. Stress- und fütterungsbedingte Veränderungen erreichen aber nicht das Ausmaß wie z. B. bei der klinischen Ketose. 15. Eine klinisch-chemische Differenzierung reaktiv-entzündlicher und degenerati-ver Leberveränderungen ist mit den Parametern ASAT, GGT und Gesamtlipi-de möglich. Die ALAT verdeutlicht den Schweregrad von Leberschäden. 16. Triglyceride und Gesamtlipide widerspiegeln unterschiedliche Fütterungsin-tensität peripartal nur gering. Der FFS-Triglycerid-Quotient korreliert zwar eng mit dem Leberfett, rechtfertigt diagnostisch den Bestimmungsaufwand aber nicht. Blutglucose und Leberglycogen stehen zum Leberfett in negativer Be-ziehung. Gesamteiweiß, Harnstoff, Creatinin, Albumin und Cholesterol lassen nur in Einzelfällen bzw. nur bei schweren Leberalterationen gerichtete Kon-zentrationsabweichungen erkennen. 17. Zur Diagnostik von Leberschäden sind unter Berücksichtigung praktischer As-pekte zu empfehlen: - für den Tierarzt in der Praxis: die Leberschwimmprobe - für BIV und vergleichbare Einrichtungen: 1. Stufe - Bilirubin und Ketonkörper (gegebenenfalls differenziert) 2. Stufe - zusätzlich FFS, GLDH, GGT, ASAT, (ALAT) 3. Stufe - histologische Untersuchungen von Leberbioptat, Leberlipide, -glycogen, gegebenenfalls unter Klinikbedingungen Leberfunktionsproben (Bromsulphthalein, Indocyaningrün) 18. Nicotinsäure zeigt bei Futterentzug sowie im peripartalen Zeitraum günstige Effekte auf den Kohlenhydratstoffwechsel wirkt antiketogen, senkt den Biliru-binspiegel, schränkt aber die Lipolyse peripartal nicht nachhaltig ein. Nicotin-säureamid hat peripartal die gleichen Wirkungen. Die Anwendung der Nicotin-säure ist besonders zur Pro- und Metaphylaxe der Ketone zu empfehlen, ihre begrenzte Wirkung auf die Lipolyse unterstreicht aber mit Nachdruck, dass der Verhütung einer gesteigerten Lipolyse mit Leberverfettung alle Aufmerksam-keit zu widmen ist. 19. Dehydrocholsäure (Biliton®) beeinflusst den Stoffwechsel von Milchkühen postpartal durch Senkung der Bilirubin-, BHB- und FFS-Konzentrationen sowie ASAT-Aktivitäten günstig. Gleiche therapeutische Effekte können bei der Be-handlung von Kühen mit Ketose und Indigestionen erzielt werden. Biliton® kann ergänzend zur Leberschutztherapie zur Behandlung von Leberkrankhei-ten empfohlen werden. Bei sekundären Stoffwechselveränderungen ist die Elimination der primären Störung Voraussetzung für den Therapieerfolg. 20. Phenylbutazon® beeinflusst als Prostaglandin-Synthesehemmer den Fett-stoffwechsel. In der ersten Woche p.p. appliziertes Phenylbutazon® hat auf den Stoffwechsel, die Milch- und Fruchtbarkeitsleistungen negative Auswir-kungen. Sein Einsatz sollte in Belastungssituationen nicht unkritisch erfolgen. 21. Der Literatur sind mögliche negative Auswirkungen von ACTH und Glucocor-ticoiden auf den Fettstoffwechsel und die Leberfunktion zu entnehmen. Ver-änderungen der FFS-Konzentrationen im Blutplasma konnten aber experimen-tell weder nach einmaliger Gabe von ACTH und Prednisolut an Schafen, noch während fünftägiger Prednisolongaben an Rindern beobachtet werden. Auch die bei den Rindern durchgeführten histologischen Untersuchungen der Le-berbioptate erbrachten keinerlei Veränderungen. 22. Gegenüber Prednisolon® (100 und 300 mg/Kuh) steigert eine einmalige ACTH-Applikation (300 IE/Kuh) die Glucosekonzentration im Blutplasma stär-ker, bis zum 3. Tag post applicationem bleibt die Glucosekonzentration nach Prednisolongabe aber auf einem höheren Niveau. Dasselbe trifft für das Ge-samteiweiß zu. Aufgrund dieser längeren Wirkungsdauer ist dem Prednisolon® therapeutisch der Vorzug z. B. bei der Behandlung der Ketose einzuräumen. 23. Aus den Untersuchungen geht insgesamt ein häufiges Vorkommen von Lipi-dablagerungen in der Leber von Rindern verschiedenen Ursprungs hervor. Ih-re Diagnostik ist sicher über Leberbiopsie bzw. weitgehend sicher über die Konzentration der FFS, des Bilirubins und des BHB im Blutplasma möglich. Die Bedeutung der Lipidablagerung für den Gesamtorganismus sowie die Rol-le hormoneller Dysfunktionen für die Entstehung von Leberschäden bedürfen weiterer Bearbeitung. Auch zur Therapie von Leberschäden sind neue Unter-suchungen erforderlich.
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44

Štulrajterová, Lujza. "Vlastnosti vláken na bázi polyhydroxybutyrátu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376819.

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Táto práca sa zaoberá zvlákňovaním biopolymérov z taveniny. V teoretickej časti sú zhrnuté doterajšie poznatky o zvlákňovaní poly(3-hydroxy butyrátu) (PHB) a poly(mliečnej kyseliny) (PLA). Následne boli zvláknené polymérne zmesi na báze PHB s rôznym zložením, čo umožnilo štúdium vplyvu PLA, zmäkčovadiel a ich množstva na vlastnosti pripravených vlákien. Boli použité tri komerčné zmäkčovadlá (ATBC, PEG, A6) a dva experimentálne syntetizované. Zvláknenie bolo prevedené na troch rôznych zvlákňovacích linkách. Konvenčné zvlákňovacie linky s odťahovými rýchlosťami nad 150 m/min sa preukázali ako nevhodné pre spracovanie našich zmesí. Kvôli nedostatočnej pevnosti taveniny sú potrebné nízke odťahové rýchlosti. Boli pripravené vlákna s dĺžiacim pomerom 6,4; ktoré boli následne analyzované pomocou GPC, MDSC a ťahovej skúšky. Na základe nameraných teplôt skelného prechodu zmäkčovadlá ATBC a PEG vykázali lepšiu schopnosť zmäkčiť skúmané PLA/PHB zmesi. Vlákna obsahujúce A6 vykazovali najvyššiu pevnosť v ťahu (250 MPa) a modul pružnosti (2,7 GPa). Nakoniec bol skúmaný vplyv starnutia, tepla a vriacej vody na mechanické vlastnosti týchto vlákien.
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45

Melčová, Veronika. "Modifikace polymerních směsí na bázi polyhydroxybutyrátu a jejich vlastnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316138.

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Teoretická část této diplomové práce popisuje vlastnosti a možnosti modifikace poly(3-hydroxybutyrátu) (PHB) a amorfní poly(mléčné kyseliny) (PLA) a jejich směsí. V experimentální části je studována reaktivita Joncrylu, Raschigu a fosfitových činidel trifenylfosfitu, tris(nonylfenyl) fosfitu a difenylisodecylfosfitu s čistým PLA a PHB. Raschig, oligomerní aditivum na bázi polykarbodiimidu, prokázal v množství 2hm. % zvýšení viskozity taveniny obou polymerů, a proto byl použit k přípravě směsí o pěti hmotnostních poměrech PHB/(PHB+PLA). Vzorky s Raschigem a odpovídajícími nereaktivními vzorky byly studovány pomocí reologie, gelové permeační chromatografie a modulované diferenční kompenzační kalorimetrie. Výsledky naznačily reakce Raschigu v PHB/PLA směsích vedoucí k rozvětveným strukturám. Rychlost reakce však není nedostatečná ke kompenzaci poklesu viskozity v důsledku degradace při zpracování. Následně zůstává nezreagované množství Raschigu v matrici. Na základě těchto zjištění se dospělo k závěru, že Raschig se chová spíše jako relativně účinný stabilizátor reologických vlastností, než jako činidlo pro záměrnou modifikaci struktury směsí PHB/PLA. Za účelem studia mechanických vlastností těchto směsí byly ve dvoušnekovém extrudéru připraveny vzorky plastifikovány acetyltributylcitrátem.
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46

Matthews, Geoffrey Mark. "Short-chain fatty acid modulation of apoptosis in gastric and colon cancer cells." 2007. http://hdl.handle.net/2440/44402.

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Introduction: Gastric and colon cancer are major causes of mortality and morbidity worldwide. Gastric cancer is often detected at an advanced stage and current chemotherapeutics are only modestly effective against this neoplasm. Novel chemotherapeutics, chemopreventive agents and treatment strategies are required to prevent and treat gastric cancer. The ideal method to eliminate cancer cells may be the induction of apoptosis, further preventing cell proliferation and tumour growth. Recently, short-chain fatty acids (SCFAs) butyrate and propionate have been investigated as potential chemotherapeutic agents, particularly in colon cancer. Butyrate is reported to induce apoptosis in colon cancer cells and is demonstrated to modulate intracellular redox state by altering the levels of an antioxidant, glutathione (GSH). GSH availability is controlled by the oxidative pentose pathway (OPP). Very few studies have investigated the effects of butyrate on cell types other than colon cancer cells, and even less is known regarding the effects of propionate. This thesis investigated the potential for SCFAs to induce apoptosis in a gastric cancer cell line, Kato III, compared to the colon cancer cell line, Caco-2. Cell cycle regulation, OPP activity, GSH availability and glucose metabolism were also assessed. Methods: Initial studies developed a new technique to measure 1-13C-D-glucose metabolism. Following this, Kato III and Caco-2 colon carcinoma cells were treated with butyrate or propionate (1mM, 5mM or 10mM) or a 5mM combination of both SCFAs. The induction of apoptosis and cell cycle alterations by these SCFAs were assessed using flow cytometry. OPP activity and GSH availability were assessed in both cell lines using colorimetric techniques. Butyrate metabolism was assessed using 13C-butyrate. Results: Butyrate and propionate significantly induced apoptosis and G2-M arrest in Kato III and Caco-2 cells, although to a significantly greater extent in the latter cell line. Moreover, butyrate induced apoptosis to a significantly greater extent than propionate, in both cell lines. SCFA treatment led to the significant up-regulation of OPP activity in both cancer cell lines while GSH availability was significantly reduced. Glucose metabolism was initially increased by all SCFA treatments, however, 72hr butyrate treatment led to its reduction. Importantly, glucose metabolism was measured using a new technique developed within this thesis. The rate of butyrate metabolism was demonstrated to correlate with the sensitivity of each cell line to this SCFA. Conclusions: This thesis provides evidence that SCFAs, particularly butyrate, induce apoptosis in gastric and colon cancer cells in vitro. The response of cancer cells to SCFAs appears complex, and involves multiple distinct mechanisms and pathways, including p53, Fas, changes to intracellular redox state and glucose metabolism. The capability of butyrate to induce apoptosis also appears to be directly related to the rate of its metabolism. Butyrate has the potential to be utilised as an adjunctive therapy for the treatment of gastric cancer and colon cancer.<br>Thesis (Ph.D.) -- School of Molecular and Biomedical Science, 2007
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47

Sewnarain, Reshan. "Multipurpose separation and purification facility." Thesis, 2001. http://hdl.handle.net/10413/5827.

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A waste acid stream is being produced by a local petrochemical company (SASOL) at a rate of 10 000 -12 000 tons per annum and contains approximately 44-mole % butyric acid, 20 % isobutyric acid and 10 % valeric acid. Whilst this stream is currently being incinerated, SASOL has requested an investigation into the possibility of separating and purifying butyric acid and isobutyric acid from this waste acid stream. The goal of this project was to determine a separation and purification route for butyric acid and isobutyric acid from SASOL'S waste acid stream. In order to achieve this, vacuum distillation and freeze crystallization were chosen for the recovery and purification of the acids respectively. Vapour-liquid equilibrium data for key component pairs present in the waste acid stream (propionic acid + butyric acid, isobutyric acid + butyric acid, butyric acid + isovaleric acid and butyric acid + hexanoic acid) were experimentally determined in a dynamic VLE still. The measured VLE data was successfully correlated us ing the gamma-phi approach. with the NRTL activity coefficient model representing the liquid phase and the virial equation of state describing the vapour phase. Using these equations. the VLE data obtained from the experimental work was then regressed to provide interaction coefficients for the NRTL model. which were then used in the Hysys process simulator to explore a range of design alternatives for distillation. Hysys simulations showed that greater than 80 % butyric acid and isobutyric acid can be recovered from the waste acid stream in a single distillation column containing 18 theoretical stages and an optimum reflux ratio of 3.8. The simulation was performed at a pressure of 58kPa and a maximum operating tempe rature of 150°C. Batch distillation experiments performed in a batch rectification column at 250kPa recovered more than 90% of both the butyric acid and isobutyric acid from a 450ml sample of the waste acid stream. A subsequent batch experiment concentrated the recovered acids into a distillate containing more than 95 % butyric acid and isobutyric acid combined. To investigate freeze crystallization as a suitable operation for purifying butyric acid and isobutyric acid a solid-liquid phase equilibrium curve for the system was generated us ing the Van Hoft equation. The generated curve showed that butyric acid and isobutyric acid could be theoretically purified (>98%) by operating two crystallizers at -20°C and -55°C respectively. A simple freeze crystallization experiment produced butyric acid with greater than 94% purity. An economic feasibility study conducted on the process showed that separation and purification of the acids by this process (distillation and crystallization) could create a business opportunity with revenue of approximately R47 million per annum. Preliminary estimates for capital investment amounted to approximately R5.4 million. for which the payback period was estimated at less than one year.<br>Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.
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48

Huang, Ya-Hsuan, and 黃雅萱. "Modeling and Optimization of Bio-Butyric Acid Production." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/20150923151377631555.

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碩士<br>國立臺灣科技大學<br>化學工程系<br>102<br>In this study, we constructed unstructured models to describe the kinetic of cell growth, product formation, and substrate consumption in the batch fermentation of Clostridium tyrobutyricum. All the parameters in the models were estimated by minimizing the sun of the square of weighted residues (SSWR) between the predictions of the models and the experimental data obtained from batch fermentation with different initial substrate concentrations. Based on this models, the optimal problem of bioreactor operation and operation variable were analyzed by maximizing the yield and productivity. The optimal model of the bioreactor operation is the continuous. The operation variables include the dilution rate, the bleed ratio, the feed flow ratio, the volume ratio, and the feed substrate concentration. The parameter estimation and the optimization problem were determined by Genetic Algorithm (GA).
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49

Chia-Lung, Yu, and 余佳龍. "Butyric acid production by PVA-immobilized Clostridium tyrobutyricum." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/21080601343471738064.

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碩士<br>中華大學<br>土木與工程資訊學系(所)<br>98<br>In the 21st century, the whole world must inevitably face the oil crisis. Therefore, we must find green alternative fuels of petroleum. Among all the energies derived from biomass materials, biobutanol is one of the most attractive biofuels. Biobutanol has been primarily produced by bacterial fermentation during the World War II. However, the fermentation process was unable to compete with petrochemical synthesis due to comparable substrate costs and low product yield. However, with the continuously increasing oil prices, the abundant inexpensive renewable resources as a feedstock for fermentation has resulted a renewed interest in the fermentation production of butanol. Moreover, recent advances in the fields of biotechnology and bioprocessing have made the fermentation process more mature, and the concept of a two-step fermentation process is the up-to-date best mode of production. By separating the acid (butyric acid) production from solvent (butanol) formation, we can reduce the inhibitory effect of butyric acid on butanol, thereby increasing the product yield. In this study, the two-step fermentation process was carried out for the production of butanol from glucose by Clostridium tyrobutyricum: the first step involves mass conversion of glucose to butyric acid, and the second step involves the metabolic shift from butyric acid to butanol. In this study, the immobilized Clostridium tyrobutyricum by PVA particles were conducted at the optimal conditions as follows: pH 6.0, 37oC to enhance the yield of butyric acid. The butyric acid production rate was significantly improved from 0.1 gh-1L-1 to 7.67gh-1L- 1. The results showed that: (1) cell immobilization can greatly enhance the cell concentration from 0.23gL-1 to 3 gL-1. Similar results were observed in the flask experiments. When the pH of the fermentation medium was 3.6, the immobilized cell concentration was 5.31 gL-1, which was 1.76 times of that of the suspension (3.02gL-1), suggesting the PVA immobilization particles have the buffer effect to protect cell growth in the acidic environments. (2) the use of a reflux-type packed bed system can effectively increase the butyric acid yield from 2.6 gh-1L-1 to 7.67gh-1L-1, which is far higher conventional fermentors. (3) When lactic acid is used as the carbon source, the overall conversion rate can be enhanced from 0.47 gg-1 to 0.85gg-1. (4) In the kinetic study, based on the reaction mechanisms, and appropriate reductions were taken of the simulated data, we can ontain the maximum reaction rate (Vmi) and half saturation coefficient (Kmi) to accuratly estimate the maximum yield of butyric acid when lactic acid is used as the substrate.
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50

Wei, Ming-zheng, and 衛明正. "Influence of acetic acid, butyric acid and ethanol on biohydrogen production." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/00712675879975264619.

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碩士<br>國立高雄第一科技大學<br>環境與安全衛生工程所<br>94<br>ABSTRACT During the process of hydrogen fermentation, there are quite a few intermediates generated mainly, acetic acid, butyric acid, and ethanol. These materials not only cause pH drop, also affect microbial activity. Certainly, metabolism is also impacted by other environmental factors as pH, hydraulic retention time, food/solids …etc. However, most of current researches focus on operational factors instead of self-generated intermediates. This study emphasized on the addition of intermediates (acetic acid, butyric acid, and ethanol) in the initial stage to determine the impact of them to the hydrogen fermentation by means of batch and continuous tests. The experiment was composed of two batch tests and a continuous test. Individual acetic acid, butyric acid, and ethanol was added to batch reactors with designed concentrations, pH, and temperature to determinate the optimal condition for individual material in batch test I. The three elements were proportionally mixed based on the optimal condition from the batch test I to determine the optimal mixing ratio in batch test II. Finally, the result from the previous test was examined by a continuous test. The result indicated that in the range of 500-8000 mg/L, the addition of these three materials affected microbial activity with different degree. The maximum hydrogen production potential and rate for individual acetic acid, butyric acid, and ethanol occurred the same at 8000 mg/L at 55℃. However, they were 5000, 5000, and 3000 mg/L at 37℃. In the range of 4.5-6.5, Hydrogen production increased and lag period shortened as pH approached 6.5. It showed a controversy situation as pH decreased. Based on regression analysis, pH had more impact than the three materials on hydrogen fermentation. The mixing study revealed that the order of hydrogen production potential at 37℃ was as follows; Sodium acetate + butyric acid > sodium acetate + butyric acid + ethanol > individual sodium acetate, butyric acid, or ethanol. The maximum potential of 4.7 ml-H2/g-COD occurred as sodium acetate and butyric acid coexisted with concentrations at 3700 and 1300 mg/L. Based on the previous optimal concentration and HRT at 4 hr and pH at 5.5, the continuous test demonstrated that the hydrogen production increased up to 19%. It did not show a clear trend at 55℃ as compared with that of 37℃. However, as the coexisted sodium acetate and ethanol were controlled at 5920 and 2080 mg/L, the potential increased as butyric acid decreased and reached a maximum of 4.3 ml-H2/g-COD.
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